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Synthesis, properties and product of hydration of strontium aluminate cement
Kocián, Karel ; Bartoníčková, Eva (referee) ; Ptáček, Petr (advisor)
This diploma thesis deals with non-traditional binder, which is strontium aluminate, with his preparation and hydration. The behaviour of binary and ternary mixtures of strontium-calcium-barium aluminates was also studied. These aluminates were prepared by firing an equimolar mixture of aluminum oxide and the appropriate carbonate. Samples prepared this way, including their mixtures, were characterized by analytical methods such as X-ray diffraction analysis (XRD), thermal analysis with evolved gas analysis (TG-DTA and EGA), scanning electron microscopy (SEM), infrared spectroscopy (IR) and calorimetry, with the greatest importance for the study of the hydration process.
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Determination of selected metals in edible mushrooms in the Kladno district
ŠIMŮNKOVÁ, Eliška
The aim of this work was to determine the concentrations of rubidium, zinc, iron, copper, strontium and manganese in samples of edible mushrooms and to compare our results with other studies. The literary research contains brief information about mushrooms, soils, metals, used analytical method and research site. During the summer months of 2020 and 2021 twelve samples of seven edible mushroom species were collected from the forest between the former mines of Kladno for the purpose of the practical part. The whole practical part of the bachelor thesis was performed in the laboratory of the Department of Applied Chemistry, Faculty of Agriculture and Technology of the University of South Bohemia in České Budějovice. Measured values were recorded in tables and statistically processed. Through analysis we found out that a parasol mushroom belongs to mushroom species with the highest ability to accumulate metals. Among the analyzed samples we found the highest content of iron (1148 mg/kg), copper (150 mg/kg) and the second highest of manganese (339 mg/kg). On the other hand the least able to cumulate metals between analyzed mushroom species was red cracking bolete which contained the lowest contents of manganese (15 mg/kg) and strontium (1,6 mg/kg). The stink snake is worth mentioning because of its high strontium (10,1 mg/kg) and manganese (643 mg/kg) accumulation. Measured manganese content significantly exceeded the values measured in other analyzed samples.
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Determination of selected metals in soils and mushrooms in the vicinity of the D1 highway.
HORÁKOVÁ, Tereza
The aim of the bachelor thesis was to determine the concentrations of heavy metals in edible mushroom samples and underlying soils. The elements measured were mainly copper, iron and zinc, followed by manganese, strontium and rubidium. The literature search contains brief information on each element and their content in soils and fruiting bodies of mushrooms in other studies. The theoretical part also includes chapters on fungi, soils and their contamination, the effect of vehicular traffic on the heavy metal content of soils and the used analytical method, which was atomic absorption spectrometry. For the practical part, 24 samples of eight different species of edible mushrooms were collected in the autumn of 2020 and 2021 in the vicinity of the D1 motorway. As part of the collection, the soil beneath the mushroom was also sampled to a depth of approximately 15 cm. The samples were first perfectly dried, then processed by microwave digestion, and finally analysed by AAS. All work was carried out in the laboratories of the Department of Applied Chemistry, Faculty of Agriculture and Technology, University of South Bohemia in České Budějovice. The results of the measurements were tabulated and processed statistically and graphically. Finally, they were evaluated in a discussion. The analysis showed that birch and birch goosefoot accumulate the least heavy metals in their fruiting bodies. The spruce budworm, the pink toadflax, the celandine and the brown mushroom accumulate metals on a large scale. In total, 4.2-45 mg.kg-1 dry weight Cu, 97,4-4166 mg.kg-1 Fe, 52,1-338,7 mg.kg-1 Zn, 3-61,4 mg.kg-1 Mn, 1,3-7 mg.kg-1 Sr and 7,7-300,9 mg.kg-1 Rb were measured in mushrooms. In soils, the values were as follows: 5,2-78,6 mg.kg-1 Cu, 2 965-41 983 mg.kg-1 Fe, 25,8- 174,2 mg.kg-1 Zn, 49,7-1 868 mg.kg-1 Mn, 6,2-25,2 mg.kg-1 Sr and 12,2-114,5 mg.kg-1 Rb in dry weight. These results show that strontium was the least represented heavy metal studied and iron was the most represented.
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Determination of selected metals in edible mushrooms in the Příbram district
DVOŘÁKOVÁ, Hana
The aim of this work was to determine the concentrations of rubidium, cesium, lithium, strontium and supplemental elements of copper, iron, manganese and zinc in samples of edible mushrooms and to compare the measured concentrations with the studies mentioned in the literary research. In addition to the results of the studies, the literary research contains brief informations about mushrooms, individual elements, the used method and the monitored location. For the purposed of the practical part, 19 samples of nine edible mushrooms species were collected from the vicinity of a lead smelter in the village of Podlesí near Příbram. The samples were the first processed by microwave digestion and then analyzed by AAS (atomic absorption spectrometry). The whole practical part of the thesis was carried out in the laboratory of the Departemnt of Applied Chemistry, Faculty of Agriculture of the University of South Bohemia in České Budějovice. The analysis results were recorded in tables, statistically and graphically processed an evaluated in the discussion. From the analysis we found the species of mushoom with the most cumulate metals ability is a toadstool rosacea. Among the analyzed samples we found the highest concentration of strontium (22,5 mg/kg), lithium (0,6 mg/kg), iron (223,0 mg/kg) and manganese (69,7 mg/kg). On the other hand, the least cumulative species was boletus brown with the lowest concentrations of copper (10,1 mg/kg), iron (29,5 mg/kg) and manganese (5,2 mg/kg) being determined. The less cumulative species was also boletus edulis, which was found to have at least strontium (2,2 mg/kg) and lithium (0,3 mg/kg). It is worth mentioning the larch bolete, in which we have determined the greatest concentration of rubidium (364 mg/kg) and cesium (11,7 mg/kg), but the least of zinc (68,7 mg/kg). Likewise, a parasol mushroom absorps copper to a large extent (255 mg/kg), but on the contrary it contained the least cesium (0,5 mg/kg) and rubidium (11,8 mg/kg).
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The content of selected group 1 and 2 metals in edible mushrooms
MÁCHOVÁ, Nikola
Edible mushrooms are able to accumulate elements, especially some heavy metals and radionuclides, in their fruiting body. This work engages in accumulation of chosen metals (Groups 1 and 2) in basidiomycete fungi and soil. The first picking happened in autumn 2017. Eleven mushroom specimens were found - several fruiting bodies of each type. The soil where the mushrooms had grown was also taken. During the other picking in autumn 2018 ten types of mushrooms were taken. The locality in the Czech Republic (Ledenice) was chosen, because these fungi were frequently found there: Agaricus campestris, Boletus edulis, Suillus variegatus, Xerocomellus chrysenteron, Neoboletus luridiformis, Leccinum rufum, Macrolepiota procera, Suillus luteus, Imleria badia, Leccinum scabrum, Lactarius deliciosus, Agaricus silvaticus, Suillus bovinus and Amanita rubescens. The chosen metals were Lithium (Li), Strontium (Sr), Cesium (Cs) and Rubidium (Rb). I used methods of atomic absorption spectrometry (AAS). In both analysis (2017 and 2018) the largest content of Lithium was recorded in Agaricus campestris fruiting body (2.3 mg/kg and 1.6 mg/kg) and the largest content of Strontium in Leccinum rufum (3.7 mg/kg and 6.6 mg/kg). It was shown that varieties of the Bolete family demonstrated the biggest accumulation of Rubidium (Boletus edulis 519 mg/kg, Neoboletus luridiformis 398.6 mg/kg). The biggest content of Cesium (about 1.1 mg/kg) was recorded also in this family.
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Synthesis, properties and product of hydration of strontium aluminate cement
Kocián, Karel ; Bartoníčková, Eva (referee) ; Ptáček, Petr (advisor)
This diploma thesis deals with non-traditional binder, which is strontium aluminate, with his preparation and hydration. The behaviour of binary and ternary mixtures of strontium-calcium-barium aluminates was also studied. These aluminates were prepared by firing an equimolar mixture of aluminum oxide and the appropriate carbonate. Samples prepared this way, including their mixtures, were characterized by analytical methods such as X-ray diffraction analysis (XRD), thermal analysis with evolved gas analysis (TG-DTA and EGA), scanning electron microscopy (SEM), infrared spectroscopy (IR) and calorimetry, with the greatest importance for the study of the hydration process.
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