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Powder metalurgically prepared materials based on Zn and Ca
Morcinek, Tomáš ; Hasoňová, Michaela (referee) ; Doležal, Pavel (advisor)
The topic of this bachelor thesis is a process of preparation and characterization of bulk material from zinc and calcium powder mixture by hot pressing. Materials thus prepared were evaluated in terms of their microstructure and physical-mechanical properties. The influence of calcium content in the material on physical-mechanical properties of the resulting structure was observed. The solution is focused on exploration of the influence of material composition in the process of preparation of bulk material, and description of these processes from the physical-chemical point of view on the structure formation and the resulting properties of the material.
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Phosphorus forms in river sediments
Schrimpelová, Kateřina ; Hrich, Karel (referee) ; Malá, Jitka (advisor)
Two main mechanism of immobilization of phosphorus in sediments are formation of insoluble phosphates of Ca, Mg, Fe, Al, and sorption. Phosphorus can be also immobilized as organic phosphorus contained in the biomass. This thesis is focused on searching of relationships between total, organic and inorganic phosphorus and iron, calcium and organic matter content in fluvial sediments. Within the framework of this thesis, samples of sediments have been collected and analyzed. The measured values have been filled by the data measured at the Institute of Chemistry in the years 2011-2012. Total number of samples is 48. Data have been statistically analyzed by Student’s t-test at the = 0,05 and = 0,01 levels of significance. The relationships between total phosphorus and iron and organic matter have been proven. Also the relationship between organic phosphorus and organic matter content has been proven and surprisingly the correlation with iron, too. The inorganic phosphorus indicated significant relationship with iron, but no significant relationship with the calcium content. At last there has been proven the correlation between inorganic phosphorus and the organic matter content.
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Preparation processes of Mg and Ca based powder materials
Jakůbek, Zdeněk ; Březina, Matěj (referee) ; Hasoňová, Michaela (advisor)
Bachelor thesis is focused on preparation of Mg-Ca material prepared from magnesium powder and calcium particles by hot pressing. Materials were characterized by microstructure and physically-mechanical properties. The influence of pressing temperature and the influence of calcium content was evaluated from final material properties. Obtained results serve to optimize these parametres.
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Treatment of bilogical waste from egg processing
Zich, Jan ; Brummer, Vladimír (referee) ; Máša, Vítězslav (advisor)
The main target of this final thesis is to compile possible uses of eggshell waste with emphasis on pharmaceutical industry. Firstly, the common handling of this waste, including legislation, is described. It is also explained what eggshell waste is mainly composed of – eggshell containing calcium and eggshell membrane rich on collagen and other substances. In addition, various ways of using eggshell waste are presented and evaluated, including manufacture of pharmaceutical products. Finally, a search for commercial solutions, patents and other sources dealing with the process of processing egg waste is carried out. It showed that although there are many patents, the offer of equipment for this purpose is very limited on the market. The acquired knowledge is used in the design of a unique process line enabling processing of both components of eggshell waste as pharmaceutical products.
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Interactions of metal ions with humic substances
Obručová, Kateřina ; Smilková, Marcela (referee) ; Klučáková, Martina (advisor)
This bachelor thesis is focused on humic substances, especially fulvic and humic acids. It deals with their genesis and subsequent extraction from nature materials. There are described not only physical and chemicals properties, structure of humic and fulvic acid, but also their reactivity. There is also described the method od isothermal titration calorimetry, which was subsequently used to study of interaction fulvic acid with selected metal ions (Cu2+, Ca2+, Mg2+). From the resulting titration data were determined values of reaction enthalpy, which was then compared with model complexes. From the resulting graphs, it was possible to determine when the reaction reached its maximum, the state when all the binding sites were full. Heat values were determined for this condition.
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The spectroscopy of a cloud of Calcium atoms for the experiment of laser cooling
Grim, Jakub ; Pham, Minh Tuan (referee) ; Číp, Ondřej (advisor)
The thesis is focused on the research on methods of generating calcium atoms into ion traps. To be specific, it is a pulse laser ablation method and generating by the calcium heat oven heated by electric current, which is currently being used. Part of the thesis is the design of experimental apparatus for the generation of calcium atoms including vacuum and optical assembly and subsequent experimental assembly itself according to design. At the end, there is an experiment, where is used electric current for heating the oven, ablation laser for ablation of calcium atoms and fluorescence spectroscopy for detection of generated neutral calcium atoms.
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Eliminace výskytu vajec s poškozenou skořápkou u nosných hybridů na konci snášky
Horník, Radek
The deterioration of eggshell quality depending on the age of the laying hens causes significant economic losses for table egg producers. The aim of the experiment was to determine whether feeding vitamin D3 in the form of 25-hydroxyvitamin D3 would improve eggshell quality after 46 weeks of flock age. Two houses with flocks of Lohmann Brown-Classic laying hens housed in enriched cage technology were included in the observation. Both houses were fed the same feed mixture from the same supplier. From 38 weeks of age onwards, eggs were collected at regular two-week intervals in a number of 60 eggs from each house for each observation. Egg weight and eggshell strength, weight and thickness were determined for these eggs. From the 46th week onwards, 25 hydroxyvitamin D3, its hydroxy analogue, was started in the feed mixture in addition to vitamin D3 at one house. Monitoring of the above parameters was continued until the 67th week of age. It was found that the eggs were lighter on the shed where 25 hydroxyvitamin D3 was fed (P < 0,001), which was due to the fact that the eggs were conclusively lighter on this shed before the experimental intervention (P < 0,05). The egg weight was closely related to the eggshell weight, which was also conclusively lower on the experimental shed (P < 0,05). There was no conclusive difference in eggshell strength and thickness between the sheds. Egg and eggshell weight and shell thickness were significantly influenced by flock age (P < 0,001). There was no positive effect of 25 hydroxyvitamin D3 on eggshell quality.
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Analýza obsahu významných nutrientů v tropickém ovoci a v jejich škůdcích
Remencová, Julie
The diploma thesis is focused on analysis of selected elements of tropical fruits and their pests. The aim of the thesis was to find a relationship between mineral content of tropical fruits and their pests and to clarify whether the found correlations can be used for targeted pest management. The mediterranean fruit fly (Ceratitis capitata) and peach fruit fly (Bactrocera zonata) are one of the most dangerous and economically important species of Tephritidae family causing significant economical looses estimated in hundreds of millions of dollars per year. The theoretical part focuses on general description, production and consumption, chemical content and importance of individual analysed tropical fruit species. Literature review deals with selected elements – calcium, magnesium, iron, zinc, manganese and copper from the point of view of importance in human nutrition. The practical part describes analyses of the above mentioned elements using flame absorption spectrometry in samples of mango (Mangifera indica), mandarin (Citrus unshiu), kaki (Diospyros kaki) and pomegranate (Punica granatum) and samples of two fruit fly species C. capitata and B. zonata. From the correlations of elements contents in tropical fruits and their pests follows that the determination of calcium can be used for identification of the origin of the pest because a significant correlation was found only between the content of calcium in mandarin and C. capitata fed on mandarin.
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