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Taxonomic position, phylogenetic relationships and metal resistance of green algae dominating in phytoplankton of two acid lakes
Barcyte, Dovile ; Nedbalová, Linda (advisor) ; Hašler, Petr (referee)
The aim of this diploma thesis was to reveal the taxonomic position and phylogenetic relationships of the dominant planktonic algae in two acid metal-rich lakes (Hromnice Lake and Plešné Lake, Czech Republic) and to compare these isolates with other closely related strains with the focus on the tolerance to various toxic metals (Cr, Al, Cu, Mn, Zn, Hg). The phylogenetic analyses showed that both strains belong to species Coccomyxa simplex. It was the first evidence that specifically this species is capable to become the dominant phytoplankton alga in the extreme environment of acid lakes with increased supply of phosphorus. Based on 18S rDNA analysis, four independent phylogenetic lineages were revealed within the genus Coccomyxa with three of them containing isolates from acid freshwaters. Furthermore, new strains of the recently described species Coccomyxa polymorpha were found growing in various chemical solutions. The toxicity test revealed that Coccomyxa simplex strains isolated from Hromnice and Plešné lakes did not show any peculiar resistance to increased metal concentrations. A significantly strain-specific response was recorded in case of aluminum, however, it was not related to the concentration of this metal in the original habitat. The ability to thrive in extreme habitats is probably...
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Application of Atomic Absorption Spectrometry for Determination of Selected Elements from Potential Ecological Burden Area
Juránková, Lada ; Hraníček, Jakub (advisor) ; Šíma, Jan (referee)
This work is focused on the determination of selected (chemical) elements (Fe, Mn, Zn, Cr, Na, K, Mg a Ca) in a potential ecological burden area using flame atomic absorption spectrometry as a detection technique. A potential ecological burden is represented by tires which are used as a construction material or as an environment surrounding for growing decorative and consumable plants. Analytes were determined in plant origin samples. Firstly, the samples were dried in a laboratory electric dryer. The weighted amount of a dried sample (approximately 0.2 g) was digested inside a microwave decomposition device with an addition of nitric acid and hydrogen peroxide. An optimization of experimental parameters was done for each of the elements before sample measuring. A burner height was optimized and 8 mm height was chosen as a optimum for most elements. Under the optimum condition basic characteristics were measured for each element separately. These characteristics included limits of detection that were: 0.05; 0.01; 0.08; 0.21; 0.02; 0.01; 0.01; 0.01 mg L-1 for the following elements: Fe, Mn, Zn, Cr, K, Ca, Mg and Na, respectively. The limits of quantification, sensitivity and repeatability were determined for each element as well. A significant attention was paid to the content of zinc in the studied...
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Determination of selected elements in plant extracts by atomic absorption spectrometry
Rydlová, Lenka ; Hraníček, Jakub (advisor) ; Kratzer, Jan (referee)
The aim of this bachelor thesis was to determine selected elements (Na, Mg, K, Ca, Zn, Se) in plant extracts and juices by atomic absorption spectrometry using different types of atomization. Each method has been optimized for determination of the mentioned elements. For flame atomization it has been used optimization of height of the primary radiation from the hollow cathode lamp over the edge of the burner. The height was generally between 6.0 and 8.0 mm. Then there have been optimized flow of each component of the flame (acetylene, air, nitrous oxide) and it has been set location of the hollow cathode lamp and the flame. Under the optimized conditions basic characteristics describing the method of the determination of mentioned elements have been measured (LOD for sodium 2.13 µg L-1 , for magnesium 2.44 µg L-1 , for potassium 11.3 µg L-1 , for calcium 15.6 µg L-1 , for zinc 6.04 µg L-1 , for selenium 0.34 µg L-1 ). In the next part of the thesis the optimized methods have been used for measuring concentration of all elements in real samples. After the preparation of the samples including dilution, addition of various reagents etc., they have been atomized by flame in an atomic absorption spectrometer (Na, Mg, K, Ca, Zn) and determined, or converted to a volatile compound (Se) and determined by...
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Determination of selective transition metals using electrochemical generation of volatile species with AAS detection
Mlejnek, Tomáš ; Hraníček, Jakub (advisor) ; Červený, Václav (referee)
The aim of this bachelor's thesis is to study the possibilities of electrochemical generation of volatile forms of copper, nickel and zinc with atomic absorption spectrometry detection. The electrochemical generation of volatile compounds were set in continuous flow analysis. A laboratory made on-membrane electrolytic cell with platinum electrodes was used for all experiments. Optimization of different conditions for electrochemical generation for specified analytes was determined via empiric methods. Optimized parameters were as follows: flow rate of carrier gas and electrolyte and generation current. The calibrations under the optimal values for both copper and zinc were measured. Other extended measurements were performed with zinc. For example, the optimization of electrolyte concentration, the influence of the atomization temperature, reversing polarity of the electrodes, the flow rate of electrolyte, the influence of salts as electrolytes, influence of DDTC, Antifoam B and oxygen addition. Possibilities of determination of zinc compounds by electrochemical generation were investigated at the end. Key words Electrochemical generation, volatile compounds, atomic absorption spectrometry, non- membrane flow-through electrolytic cell, quartz tube atomizer, copper, nickel, zinc
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The Study of ZnO Crystal Growth in Supersaturated Alkaline Solution
Bannert, Tomáš ; Máca, Josef (referee) ; Chladil, Ladislav (advisor)
This thesis deals with the study of growth of zinc oxide crystals from supersaturated solutions using a scanning electron microscope and XRD methods. The work is divided into a theoretical and an experimental part. The theoretical part analyses issues related to the principle of operation of electrochemical cells with an emphasis on Ni-Zn batteries and phenomena limiting the life and efficiency of Ni-Zn batteries with a focus on phenomena that affect precipitation processes of zinc oxide crystals. It also analyses and compares the appropriateness of the methods that have been used to study the growth of the prepared zinc oxide crystals. The experimental part describes the preparation of a supersaturated solution, the process of each analysis and its evaluation. The results of each method are compared with the theoretical assumptions and among themselves. The experimental part also contains a chapter dealing with the design of in situ X-ray diffraction analysis methods of the obtained zinc oxide crystals.
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Obsah zinku, mědi a jódu v mléce krav
JAKEŠOVÁ, Jitka
Milk and dairy products are one of the most important sources of essential trace elements in human nutrition. My thesis provides informations about the content of zinc, copper and iodine in milk during the lactation and also includes the impact of other factors on the content of elements. The experiment includes dairy cattle breedings from Hořepník and Chyšná which are located in the region Vysočina. Another breeding is from Haklovy Dvory. It is located in southern Bohemia. Milk samples were taken in the relation to performance monitoring. During the period 25 to 132 days of lactation were taken 90 samples of milk from the Hořepník breeding. From breeding Chyšná were taken 78 samples of milk in the period of 11 - 89 days of lactation and from breeding Haklovy Dvory 81 samples of milk during the period 23 to 244 days of lactation. Copper and zinc content in milk was determined by atomic absorption spektrometry. The iodine content in the milk was set by spectrometry after incineration alkaline by Sandell-Kolthoff. The average zinc content in the milk was 3.59 ? 1.15 mg-l-1. The average copper content in milk was 0.14 ? 0.12 mg-l-1and the average content of iodine in the milk was 0.18 ? 0 06 mg-l-1. The greatest variability in milk was proved to copper (V = 82,65%), the lowest zinc (V = 32,05%). The greatest effect of the duration of lactation was observed in breeding Hořepník (Zn: rxy = -0,430, Cu: rxy = -0,425, I: rxy = 0,326). The influence of the duration of lactation was insignifant in the breeding Haklovy Dvory and Chyšná. Cow's milk, according to our results, supply the iodine accounts from 19,2% for men and 52,4% for women. The milk supply the zinc accounts from 5,2 % for men and 7,2 % for women, and copper from 2,5% for both sex.
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Preparation processes and properties of porous zinc material
Moleková, Kristína ; Březina, Matěj (referee) ; Hasoňová, Michaela (advisor)
Bachelor thesis occupy with preparation of porous material from zinc powder by cold pressing, cold pressing followed by sintering and hot pressing. This thesis contain both preparation of bulk material, and charakterization of materials based on the compaction process conditions. Impact of pressing process on subsequent progress of sintering and final attributes of materials is evaluated. Bulk material is characterized considering to structure, porosity, and physical-mechanical properties. Properties of final metarial will serve to optimize conditions for process of pressing and sintering.
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The content of selected metals in soil as an indicator of contamination due to the road traffic
VOLAVKA, Tomáš
The soil, as a part of ecosystem, is permanently endangered by pollution and exposed to degradation. A large share on this pollution has a human. This problem is caused mainly by industrial production, agriculture and transport. Intensive chemical maintenance is necessary during winter. It is because of better driving on the roads. Chemicals gradually soak into the soil and contaminate it. This master thesis deals with the analysis of soil samples from close proximity of road from Veseli nad Luznici to Trebon. There was analyzed the concentration of copper, sodium and zinc. Samples were collected in two depths: from 0 to 15 cm (surface sample) and 15 to 30 cm (subsurface sample). The mentioned metals were analyzed by atomic spectrometry. The measured value concentration of copper was between 2.24 mg-kg-1 and 84.35 mg-kg-1, the sodium concentration was from 11 mg-kg-1 to 1 697 mg-kg-1 and the zinc concentration was in the range of 9 mg-kg-1 526 mg-kg-1. The highest concentration of copper (84.35 mg-kg-1) was found in the subsurface sample taken from the immediate proximity of the railway in February 2017. The highest concentration of sodium (1 697 mg-kg-1) was measured near the road in February 2016. The highest concentration of zinc (526 mg-kg-1) was measured near railway in October 2015.
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Contamination of soils with selected metals due to the railway transport
VONDRUŠKA, Jan
This work deals with the determination of metals in soils taken close to the railway. Copper, zinc, nickel and chromium were selected as indicators of the environment contamination. Samples were taken from three localities in South Bohemia. These localities were chosen on the basis of different types of railway tracks (electrified and nonelectrified) and different frequency of train connection. Atomic absorption spectrometry was used for the determination of the metals. An AAS Thermo Scientific iCE 3500 spectrometer served to determine individual analytes. The highest level of copper pollution was detected for samples taken close to the railway with electrified track and with high frequency of train connection. The highest Cu concentration (66.30 mg/kg) was determined in the soil sample from 20cm depth. The highest level of zinc pollution was detected for samples taken in the distance of 3 m from the railway with electrified track and with high frequency of train connection. The highest Zn concentration (641.77 mg/kg) was determined in the soil sample from 30cm depth. The highest concentrations of other metals (Ni and Cr) were detected for the railway with nonelectrified track and with low frequency of train connection. The highest concentrations of Ni and Cr were 21.89 and 54.89 mg/kg, respectively. These concentrations were obtained for samples taken close to the railway.
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Study of physiological changes in plants under stress by zinc ions
Adam, Rostislav ; Soudek, Petr (advisor) ; Petrová, Šárka (referee)
Heavy metals are part of us life for many centuries. Some of them are for living organism neccessary, but in large amount they have toxic effects. So we should decrease amount of heavy metals in the Environment. We have many way to do it. A relatively new way are the phytoremediation. If we would use the phytoremediation, we should know, what they do in plants. We must use specific plants, which are tolerant to certain heavy metal. If we would select a suitable plant, we have to try, how heavy metals in soil solution are toxic to plants. Zinc is no expection, although it is important part of many proteins. In plants it make rusty leaves and reduct aboveground and root biomass production. In hydroponic experiment I investigated that mallow Malva verticillata was very sensitive to low additon of Zn(NO3)2. The toxic efect appeared in 2 weeks. In sorghum Sorghum bicolor zinc show expressive toxic effect at concentration 1 mmol/l. I studied six cultivars of Sorghum bicolor, DSM 14-535, Expres, Honey Graze BMR, Nutri Honey, Sucrosorgho 506 and Sweet Virginia. According EC50 I as- sessed that the most sensitive was Sucrosorgho 506 and very tolerant were Nutri Honey and Sweet Virginia. Cultivar Nutri Honey was characteristic. It had the highest ratio concentration in shoot to concentration in root. I studied...
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