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Vegetation of post-mining sites determines soil microbial community structure and soil processes
Urbanová, Michaela ; Baldrian, Petr (advisor) ; Bárta, Jiří (referee) ; Chroňáková, Alica (referee)
Vegetation of post-mining sites determines soil microbial community structure and soil processes Mgr. Michaela Urbanová Abstract The aim of this thesis, which consists of four published articles, was to investigate the effect of vegetation on soil microbial communities and processes in de novo developing soil substrate on the brown-coal spoil heaps in the surrounding of city Sokolov. Spoil material - soil clayey substrate, which had been gradually mined from the opencast brown coal mine, stratified onto spoil heaps and reclaimed by assisted afforestation with selected tree species or left for spontaneous plant succession, changes its biotic and abiotic characteristic in the course of time and particularly under the influence of plants. Changes of spoil substrate characteristics are related to the growth of plant roots and particularly also to the production of plant biomass, which is decomposed gradually and takes part of soil, where participates to soil organic matter. The process of plant dead materials decomposition and transformation is the function of the activity of soil organisms and among them notably soil microorganisms. Moreover, the presence of many of them is closely related to the presence of vegetation, whose symbionts or pathogens are. The exact mechanisms of the plant-microbes interactions...
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Synthesis of 1,4-phosphonic and phosphinic acid derivatives of cyclen
Bárta, Jiří ; Kotek, Jan (advisor) ; Vojtíšek, Pavel (referee)
Title: Synthesis of 1,4-phosphonic and phosphinic acid derivatives of cyclen Author: Bc. Jiří Bárta Department: Department of Inorganic Chemistry, Faculty of Science Supervisor: Doc. RNDr. Jan Kotek, Ph.D. Supervisor's e-mail adress: modrej@natur.cuni.cz Abstract This thesis is focused on synthesis of diphosphonic and diphosphinic derivatives of cyclen at 1,4 positions as potential MRI contrast agents. Preparation of 1,4-dibenzylcyclen was optimized in a gramme scale for synthesis of derivatives mentioned above. 1,4-dibenzyl-7,10-bis(diethylphosphonomethyl)cyclen was prepared in a gramme scale. It's fully hydrolyzed and monoester forms were prepared. 1,4-bis(diethylphosphonomethyl)cyclen was synthesized. It's fully hydrolyzed and monoester forms were synthesized. 1,4-dibenzyl-7,10- bis(phosphinomethyl)cyclen was synthesized. The carboxylic function in ester form was attached on diesterphosphonic derivative of cyclen. Altogether 8 derivatives in positions 1,4 and 7,10 of cyclen was prepared, mostly in a gramme scale and with a high yield. All compounds were characterized by NMR and MS. Key words: cyclen, phosphonate, phosphinate, sythesis, MRI
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Molecular biology and ecology of microbial decomposition of plant-derived biopolymers in forest ecosystems
Žifčáková, Lucia ; Baldrian, Petr (advisor) ; Uhlík, Ondřej (referee) ; Bárta, Jiří (referee)
The abilities of fungi and bacteria to degrade simple and complex carbon compounds derived from different sources, such as root exudates, litter, soil organic matter or fungal mycelium were studied in this dissertation. Knowledge of functional traits, especially degradation abilities of fungi and bacteria, are important for deciphering the black box of microbial functioning in topsoil and thus aiding in modeling and predicting future directions of microbial communities development in face of global changes. Among fungal cultures form culture collection representing strains with different taxonomy and ecophysiology, the ecophysiology of fungi was more important in manifestation of functional traits than taxonomy. Among bacterial isolates from the litter and soil of spruce forest, Acidobacteria were confirmed to express multiple decomposition enzymes in high rates in vitro and were also abundant and active degraders in acidic spruce forest soil. The expression of degradation capacities of both bacteria and fungi were further studied in situ in spruce forest topsoil, that represents an important environment due to the ubiquity of coniferous forests on the Northern hemisphere. There is an obvious gap of knowledge, when comes to our understanding of seasonal effect on microbial functioning, and this is...
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Small Induction Motors for Specific Applications
Bárta, Jiří ; Janda, Marcel (referee) ; Hájek, Vítězslav (advisor)
The aim of this master`s thesis is to introduce the principle of construction of a single-phase shade-pole motor and its utilization in automotive industry. It is very simple motor in its structure. The position of shading ring gives us the direction of rotation. It is used mainly when low efficiency is needed, e. g. to run electrical fans, small household appliancesor. Cheap construction is its undeniable advantage.
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Transmission mechanisms of autocross racing cars
Bárta, Jiří ; Klapka, Milan (referee) ; Mazůrek, Ivan (advisor)
This Bachelor's thesis is special technical search with concentration on creating of overview drive conceptions and transmission mechanisms at autocross racing cars. As the basis of the information there was processed the proposal of conception drive double engine arrangement for class 1.600 ccm. The whole thesis is comleted with photo-documentation of racing special cars and with their parts.
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The Use of SW Tools of Emergency Office for Solutions of Emergency Situations
Anderlová, Monika ; Fišer, Václav (referee) ; Barta, Jiří (advisor)
Information technology is integral part of crisis management nowadays. T-SOFT company developed EMOFF – information system for support of crisis management, which is unique not only in Czech republic, but also in Europe. EMOFF facilitates work and tasks of crisis managers. Professional literature and information of EMOFF are very limited or do not exist, therefore this work describes the system and creates manual of EMOFF, focused on work,usability, weaknesses and strengths of the system.
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