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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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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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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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Role of exotic woody plant species in introductions of non-native symbiontic fungi
Vlk, Lukáš ; Kohout, Petr (advisor) ; Bárta, Jiří (referee) ; Anthony, Mark (referee)
The introduction of alien microorganisms so far received much less attention compared to macroorganisms. The introduction of alien fungi is currently considered an important and understudied component of global environmental change. Outbreaks of alien fungal pathogens threaten native plant and animal communities and cause immense ecological and economic damage. The introduction of alien mycorrhizal fungi enables the invasion of their hosts and could significantly alter key ecosystem functions and the soil biogeochemistry of recipient ecosystems. Evidence suggests that the introduction of alien plants serves as a major pathway for the spread of alien fungi. The main goal of this dissertation was to significantly contribute to the understanding of the phenomenon of the introduction of alien fungi. Specifically, this work aims to (1) assess the difference in the strategy of the two most commonly introduced alien tree groups on a global scale, pines and eucalypts, to obtain suitable ECM fungal partners in new areas, (2) assess the prevailing ecology of alien ECM fungi on a global scale, and (3) determine the extent of the introduction of alien fungi associated with alien trees in the chateau parks of the Czech Republic and identify environmental factors that affect their relative abundance, richness...
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Natural enemies of the European spruce bark beetle \kur{Ips typographus}
BÁRTA, Jiří
Bark beetles (Scolitynae) are among the most important pests of forest stands, where they cause extensive damage, especially in spruce monocultures. Their negative effect is to attack the host tree, which is its source of food and at the same time provides them with space for reproduction. The bark beetle is able to have several generations per year under suitable temperature conditions. One of the most widespread is consi-dered to be the European spruce bark beetle Ips typographus. This species is able to search for weakened and abiotically damaged trees. Integrated Pest Management of forests includes several effective methods against bark beetles. The most used met-hods include the installation of feromone traps, traps trees and poisoned tripods. The European spruce bark beetle is in their population regulated by many natural enemies. From parasitoids such as Coeloides bostrichorum and Rhopalicus tutela and predators Thanasimus formicarius and Medetera spp. to pathogenic microorganisms such as entomopathogenic viruses, bacteria, protozoa, microsporidia and especially entomo-pathogenic fungi belonging to the order Hypocreales. The most important species is the fungus Beauveria bassiana, which has the greatest potential in the biological pro-tection of spruce stands.
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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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Coordination behaviour of substituted cyclen derivatives
Bárta, Jiří ; Kotek, Jan (advisor) ; Vargová, Zuzana (referee) ; Lubal, Přemysl (referee)
Magnetic resonance imaging (MRI) is one of the none-invasive techniques of human body examination. The only disadvantage of MRI is a low resolution and specificity, therefore, MRI contrast agents (CAs) are widely used in clinical practice (approximately in 40 % of all examinations). They increase not only resolution and specificity but also efficiency of the examination. The CAs consist of paramagnetic ion (Gd3+ or Mn2+ ) and strong chelator such as H4DOTA. Macrocycle cyclen (1,4,7,10-tetraazacyclododecane) is basis of many derivatives which are being used, including mentioned the H4DOTA ligand. 1,4-phosphonic or 1,4-phosphinic acid cyclen derivatives could be a better alternative to commercially available ones. In this thesis, a synthetic pathway to 5 of these novel derivatives is introduced. The protonation constants and stability constants with metals used in CAs (Mn2+ , Gd3+ ) and other selected ones using the potentiometric titrations are determined for 1,4-H4DO2P, 1,4-H2DO2POEt and 1,4-H2DO2Bn2PH . All three ligands have higher stability constant with Mn2+ - log KLM around 12, than with Ca2+ - log KLM around 8, which is the closest rival for transmetallation under physiological conditions. Strong Gd3+ -complex is formed by hexadentate ligand 1,4-H4DO2P - log KLM = 19.15, which is comparable...
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