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Interaction of group III and IV metals with Si(100) surface in temperature range from 20 to 800K
Setvín, Martin ; Ošťádal, Ivan (advisor) ; Janda, Pavel (referee) ; Klapetek, Petr (referee)
1 Title: Interaction of group III and IV metals with Si(100) surface in temperature range from 20 to 800 K Author: Martin Setvín Department: Departement of Surface and Plasma Science Supervisor of the doctoral thesis: Doc. RNDr. Ivan Ošt'ádal CSc. Abstract: Interaction of group III and IV metals with Si(100) surface was studied by STM (Scanning Tunneling Microscopy) and AFM (Atomic Force Microscopy) in temperature range from 20 to 800 K. Adsorption and hopping of single metal adatoms on Si(100)-c(4×2) reconstruction can be observed by STM at low temperatures. Activation energies and frequency prefactors for hopping of single indium atoms were measured by two meth- ods - direct STM measurement at low temperature and Kinetic Monte Carlo simulations of layer growth at room temperature. Group III and IV atoms self-assemble into single atom wide chains on Si(100) surface at about room temperature. Atomic and electronic structure of the chains was investi- gated by means of STM and dynamic non-contact AFM. Keywords: Si(100), STM, AFM, adsorption, diffusion
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Constitutional aspects of the termination of the Czechoslovak Federation
Janda, Pavel ; Gronský, Ján (advisor) ; Jirásková, Věra (referee)
- Constitutional aspects of the termination of the Czechoslovak Federation The thesis deals with problems of constitutional aspects relating to termination of the Czechoslovak Federation, which was abolished on 31.12. 1992 I have chosen this theme because I am interested in this theme since the first grade of my studium at the Law faculty. I had better access to this theme after the attendance of Scientific seminar leaded by Doc. Gronský called Slovakia in constitutional history of Czechoslovakia. The thesis uses sources available to students of Law faculty (monography, collections, university textbooks, texts of laws, articles, stenograph records, university lectures). The thesis is grounded on the synthesis of many sources with emphasis on consistent citing sources of the original authors. The thesis is composed of three chapters, which are divided into subchapters. These subchapters contain parts. In introduction I set the aim of thesis to describe the aspects of termination Czechoslovakia. For better context is in thesis genesis and development of the federation. Chapter one consists of two subchapters. There are described conditions of formation of Czechoslovak state. Chapter two consists of four subchapters, which describe Constitutional development of Czechoslovakia (1918-1989) with focus on...
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Italian Fascism in the View of Theory of Elits
Janda, Pavel ; Buben, Radek (advisor) ; Voráček, Emil (referee)
This paper summarizes the interpretations of fascism from the first half of the twentieth century. Then the paper sets two points of view and compares them. The first is the point of view of the opponents and critics of fascism, whether it would be communists or liberal democrats. These critiques are confronted with Mussolini's seeing of fascism. His conceptions are supplemented by other works of other supporters of fascism or by the official materials of fascist movement (or party). Everything is seen from the point of view of the theory of elitism.
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Control of the industrial robot with cameras
Janda, Pavel ; Obdržálek, David (referee) ; Hlaváč, Václav (advisor)
This thesis belongs to the implementation category of diploma theses. The work contributes to the EC project COSPAL, IST-2003-004176. The main goal of the project was the creation of the system of control and processing of the camera information for the assembly task. The demonstrator is used within the scope of the COSPAL project to solve a child's game - shape sorter puzzle. For solving the puzzle, the industrial robot CRS Robotics A465 was used. The robot has been available at the supervisor's place.
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Effect of substrate hydrophobicity on the electrocatalytic behaviour of phthalocyanine
Klusáčková, Monika ; Janda, Pavel ; Tarábková, Hana
In this work, the electrocatalytic activity of pyridinoporphyrazine mediator deposited on two substrates with different hydrophobicity has been presented. We focused on hydrophobic highly oriented pyrolytic graphite (HOPG) as well as hydrophilic annealed gold electrode (Au111). The immobilization of mediator has been carried out spontaneous adsorption from aqueous solution on electrode surfaces. The different hydrophobicity surface resulted in change the electrocatalytic activities of mediator to hydrogen in aqueous solution. For this purpose, electrochemical, in situ spectroelectrochemical, and ex situ microscopically characterizations have been performed. The detailed comparison of surface morphology, surface coverage, surface roughness parameters, thickness of deposited layers of mediator, and pH solution has been studied.
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Poly(methylene blue) modified carbon based electrodes for the determination of sulfhydryl-containing compounds
Zlámalová, Magda ; Janda, Pavel ; Nesměrák, K.
This research presents the study of electrochemical polymerization of phenothiazine derivative, methylene blue (MB). Electrochemical pro perties and analytical application of resulting electrocatalytically active poly(methylene blue) (pMB) have been investigated. Three various carbon-based substrates: basal plane of highly oriented pyro lytic graphite (HOPG), pencil graphite electrode (PGE) and carbon fibre micro electrode (CFE) have been used. Aforementioned electrodes modified with the polymer (HOPG/pMB, PGE/pMB and CFE/pMB) have been prepared by potential cycling in aqueous electrolyte solution containing dissolved monomeric methylene blue. Electrocatalytic activity of three developed electrode systems towards hydrogen sulphide has been compared. Developed electrodes have been further investigated as potential sensors for sulfhydryl-containing compounds.
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Strucutre and disturbance regime of the natural spruce mountain forests in the Fagaras Mts. in Romania
Sýkora, Ondřej ; Svoboda, Miroslav (advisor) ; Janda, Pavel (referee)
There is a large natural disturbance in spruce stands at the present moment in many European countries. Therefore understanding of the long-term natural processes and the impact of disturbances on the structure have a key role in the management of spruce forests. For this purpose, we have studied the structure and the historical regime mountains, which is one of the best preserved forest ecosystems in the Europe. Between 2011 and 2013 years we have founded nearly 50 research spots in the four valleys where we collected data on the structure of the forest. For purposes of reconstruction of disturbances history samples from almost 3 500 individuals of Norway spruce (Picea Abies) were taken. Data were analyzed with dendrochronological methods and descriptive statistics. Partial synchronization of disturbances with the valleys and the subsequent rise in the regeneration was detected, which shows the influence of disturbances evoked by wind and then, probably, by the increasing population of bark beetles. We noticed the importance of the disturbances (weak - strong), which directly influences the structure and creates the mosaic diversity of vegetation. The history of the oldest areas goes back for 400 years, and for the youngest - for 100 years. The volume of the deadwood in the valleys was approximately 135 m3. Overall, on the investigated spots 1380 individuals of regeneration with dominating recovery of Norway spruce (Picea Abies) were recorded, with the proportion of 76 %.
Our results show that the disturbances are partially synchronized with the landscape level and also on the level of each valley, and have a major impact on the structure and dynamic of the forest. Natural disturbances are the main factor affecting the natural regeneration of spruce forests.
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History and presence of oak stands in Europe
Kloučková, Dominika ; Bače, Radek (advisor) ; Janda, Pavel (referee)
The aim of this work is to evaluate historical human impact on the expansion of European oak stands in the past through scientific publications and to find existing limitations that affect the oak recovery ability. The European historical forest is characterized by coppicing, of which origins date back to the Neolithic period. The coppice featured vegetative renewal, in the coppice with standards there were left standards of the generative origin, often oaks. Both forms have a very long tradition in European countries. People used the sprouting capacity and the quick regeneration of oak especially for construction purposes and their need for firewood. Acorns secured the source of food for pig farming. Based on for example the ring width or pollen analysis, current methods of research permit to assess the impact of active management on the oak stands and outline the structure of primeval forests. It turned out that coppicing has a positive effect on the increment of oak standards and that the open landscape with a rich diversity of species, which features a picture of a primeval forest, was always maintained especially by a man starting forest fires. Since the mid-20th century, it was gradually transferred to the high shape of the wood, which favors generative way to recovery, and thus monocultures of often coniferous trees are created. Oak is currently health endangered tree species and its recovery is negatively affected by grazing deer (browsing), the influence of abrupt climate change, weed, pathogenic fungi of the genus Phytophthora, oak powdery mildew (Microsphaera alphitoides), tracheomycotic diseases or larvae of winter moth (Operophtera Brumata) and green oak moth (Tortrix viridana). Finally, it is inappropriately selected management that is not based on the rich history of this species and doesn´t preserve its characteristic natural properties.
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Mixed forests and its practical use for forest management
Adamec, Jiří ; Janda, Pavel (advisor) ; Mrhalová, Hana (referee)
This Bachelor thesis focuses primarily onmixed forests and their practical use for forest management. It deals with forests both in Central Europe and the Czech Republic. Issues related to forests and the effect of different influences on them, are the subject of a variety of scientific papers. Obtained knowledgeabout mixed forests could help us better understand the increasingly emerging climate change. The main factors are temperature, rapidly changing in the recent years, and the changes in average total annual precipitation and varying amounts of gases in the air. The actual composition of the mixed forests and the individual characteristics of trees have to be also taken into account. An increased incidence of pests and diseases of trees and proliferating pests that may be affected both by climate change ortree species in the stands. This paper presents the possible conversion of spruce monocultures into mixed stands It contains a lot of knowledge from various scientific papers whose main points are summarized in a form of literature review and could lead to improved conditions of our forests.
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Dynamics and stand structure of the primary mountain mixed forests in Temperate Zone (Europe)
Votava, Martin ; Janda, Pavel (advisor) ; Lábusová, Jana (referee)
The bachelor thesis mainly deals with dynamics and structure of mountain mixed forests in
the temperate zone of Europe. It provides complex view at disturbance regimes and its effect on forest ecosystems. European mixed forests dominated by Fagus sylvatica, Abies alba and Picea abies are characterized by variable wind disturbances. Wide range of severity classes and spatial patterns of disturbances influence these ecosystems, consequently, it has important influence on species composition and developmental trajectories. Partly, the bachelor thesis deals with the perspectives of forest management in context of biodiversity and climate change. The bachelor thesis was compiled as literature review from many national and international results of scientific studies. Main aim of the work was to summarize general principles about these ecosystems.
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