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Průseky pod elektrickým vedením jako šance pro světlomilné druhy organizmů
Lišková, Zuzana
In the framework of the bachelor thesis, were examined the power line corridors as a chance for heliophilous species of organisms with a focus on spiders. The aim of my bachelor thesis was to place earth traps on suitable passages of power line corridors, to deduce the influence on the observed group in researched power line corridor, in my case spiders and to discuss the optimal solution of management under the power lines. The collection of spiders took place near the village of Popůvky from May to September 2017 and was collected once a month. Eight ground traps were placed in a line perpendicular to the power lines. A total of 166 spider specimens were captured and determined. From this result 65 were juveniles and they were divided into five families and 101 were determined to 29 species. The research included a comparison of indivi-dual living demands. Xerothermic spider species were taken in the power line corridor. In addition to common species, threatened species appeared here as well. The results show a positive effect of the power line corridor on the spiders compared to the forest. According to comparison of other works, this conclusion can also be applied to other invertebrate species occurring in power line corridors.
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Evaluation of the natural recreational potential of the area Smečno - Ledce - Přelíc
Lišková, Zuzana ; Růžičková, Lenka (advisor) ; Ivan, Ivan (referee)
The thesis deals with the evaluation of the natural recreational potential of a selected area. The evaluation is based on three different methods with different approaches. Selected methods are TERPLAN, Inverse Distance Weighting IDW and Focal statistics. The evaluation was situated in the Central Bohemian Region in the territory of Smecno, Ledce and Prelic.
Input data for TERPLAN were created by vectorization of base maps. The TEPRLAN method needed to be edited for needs of selected area, because the original form of the TERPLAN is strictly focused on several landscape features. Input data for the other two methods comes from questionnaires. Landscape features were divided into five groups which each of them represent a specific sort of a recreation. These groups were rated according to the results of questionnaires. The IDW method evaluated the recreational potential on basis of distances between the centers of towns and landscape features. The result of this method is an interpolated value of recreational potential for its center. The recreational potential was counted for every town center and their merger gives a final raster layer as a result of recreational potential of whole area. The method of focal statistics was counted for mean and sum of input values. The raster layer of mean focal statistics represent a distribution of important landscape features in area. Second method of focal statistics with sum leads to the results that summarize recreational potential of each segment in area.
Results of these three methods were supplemented with field research. According to the results of all methods was selected part of area with greatest recreation potential where was situated plans to boost actual potential. These plans should bring recreation opportunities closer to the public. Outcomes of this thesis can be used as input for next strategic planning development of this area.
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Preparation of graphene nanostructures for applications
Dubnická Midlíková, Jana ; Procházka, Pavel (referee) ; Lišková, Zuzana (advisor)
The thesis deals with preparation of graphene nanostructures and their applications in the measurement of electrical transport properties of graphene. Graphene layers are prepared by mechanical exfoliation in two ways, by using adhesive tape or elastomeric film. The contacts for measurement of graphene layers resistance are fabricated by electron beam litography on exfoliated graphene flakes. Measurements of graphene transport properties take place in two environments, in air and in vacuum. Mobility and concentration of charge carriers of prepared graphene nanostructure are determined from the measured values.
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Transport Properties of Graphene Layers during Their Transfer
Gryga, Michal ; Lišková, Zuzana (referee) ; Procházka, Pavel (advisor)
This bachelor thesis is focused on the measurement of the transport properties of graphene, which was produced by chemical vapor deposition (CVD) method on a copper foil and subsequently transferred onto a silicon substrate covered by 280 nm of silicon dioxide. In this work we studied an influence of different types of copper etchants and influence of plasma cleaning of silicon substrates prior to the graphene deposition.
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Fabrication of Nanostructures and Nanodevices for Nanoelectronics and Spintronics
Lišková, Zuzana ; Červenka, Jiří (referee) ; Čech, Vladimír (referee) ; Šikola, Tomáš (advisor)
The thesis deals with preparation of graphene nanostructures and their applications in the measurement of transport properties of graphene. The contacts for measurement of resistance are fabricated by electron beam lithography on graphene exfoliated flakes, CVD graphene layers and grains. Graphene is also shaped using the same method. Resistivity of the layer, concentration and mobility of charge carriers are determined by different approaches. Hysteresis appearing in dependence of resistivity on the gate voltage is discussed as well. A significant part of the work is dedicated to monitoring the response of graphene resistance to relative humidity changes and potential use of graphene as a sensor of relative humidity.
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Aplication of SPM in study and modification of ultrathin films Pt, Co and graphene
Lišková, Zuzana ; Červenka,, Jiří (referee) ; Bartošík, Miroslav (advisor)
This diploma thesis deals with the preparation of the very thin films and their investigation by scanning probe microscopy methods. The ultrathin films of Pt on Pt(111) were created by pulsed laser deposition and the ultrathin films of Co on Pt(111) were deposited by thermal evaporation. The coverage of the substrate was much smaller than one monolayer (in order of hundredths of monolayer). The nucleation theory was verified by these experiments using so-called Onset method. Further graphene sheets were prepared on layer of Si/SiO2 by the mechanical exfoliation from the graphite crystal. The fabricated graphene sheets were studied by micro-Raman spectroscopy, microreflectometry, atomic force microscopy and similar techniques. These methods proved the thinnest graphite layers were consisted of two graphene monolayers.
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Analysis of the transport properties of graphene nanostructures
Novák, Martin ; Bartošík, Miroslav (referee) ; Lišková, Zuzana (advisor)
Graphene transport properties are analysed in this thesis. They are strongly dependent on doping with charge carriers. The number of charge carriers can be influenced by electric field, substrate or surface adsorbates. The graphene field-effect transistor (FET) has been prepared. Graphene made by chemical vapor deposition (CVD) has been con tacted through gold structures made by electron beam lithography (EBL). Dependences on electrode configuration, gate voltage and used substrate are observed.
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Schottky solar cells with interface graphene/Si modified by gallium
Hlavička, Ivo ; Lišková, Zuzana (referee) ; Mach, Jindřich (advisor)
Main focus of this bachelor thesis is on fabrication, characterization and modification of graphene-on-silicon Schottky solar cells. By transfering CVD graphene onto silicon wafer with electrodes, a basic Schottky junction was created. The junction was then modified by annealing in UHV chamber as well as by gallium deposition. Information about power conversion efficiency of such Schottky solar cells was then obtained by IV measurement. Schottky junction itself was analyzed using X-EBIC method.
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Study of interface graphene-on-silicon by EBIC method
Hammerová, Veronika ; Lišková, Zuzana (referee) ; Mach, Jindřich (advisor)
This bachelor thesis is dedicated to study of interface graphene-on-silicon located on solar cell with graphene layer. The interface was studied by EBIC method and Raman spectroscopy. Solar cells with graphene sheet was fabricated using electron litography, chemical etching and graphene made by CVD method. The thesis describes fabrication of solar cells with graphene layer, method EBIC measured on SEM and analysis of changes graphene-on-silicon interface caused by enlightenment electron beam by Raman spectroscopy. In theorethical part is described p-n junction and Schottky junction of solar cell, graphene and its fabrication, as well as EBIC method fundamentals.
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