|
|
Correlative probe electron microscopy analysis of plasma-treated gallium-doped zinc oxide nanorods
Rutherford, D. ; Remeš, Zdeněk ; Mičová, J. ; Ukraintsev, E. ; Rezek, B.
Correlative Probe Electron Microscopy (CPEM) was used to investigate the topographical and electronic emission properties of gallium-doped zinc oxide nanorods (ZnO:Ga) after low pressure hydrogen or oxygen plasma treatment. Simultaneous secondary electron (SE) and back-scattered electron (BSE) emission information from the same nanorods enabled true correlation with the topographical information obtained by atomic force microscopy (AFM). All nanorods were analyzed in-situ on the same substrate using the same experimental parameters which allowed for accurate comparison. ZnO:Ga nanorods displayed the largest SE emission intensity as well as the greatest BSE emission intensity. Hydrogen plasma treatment reduced both SE and BSE emission intensity, whereas oxygen plasma treatment only reduced SE emission. These effects may help elucidate various optical as well as biological interactions of ZnO:Ga nanorods.
|
|
|
Optimalizace webových stránek
Kašpar, Michal
This thesis is focussed on detailed processing of the optimization of web pages for web search engines (SEO). It describes the functionality of full text search engines considering the order of search results. The thesis also presents the most often myths and problems from the field of optimization which are supplemented by the right procedures according to the currently used methods and processes. Further on, the thesis is supplemented by the general outline of the process of optimization which is furthermore used and explained in detail in a practical case study. There is also mentioned the point on the issue of scoring the rate of return in optimiza-tion.
|
|
| |
|
|
A Review of the Li-ion Battery in-situ Experiments in Scanning Electron Microscope
Trochta, David ; Klvač, Ondřej ; Kazda, Tomáš
This paper focuses on the description of in-situ experiments with lithium-ion batteries in a scanning electron microscope during cycling. With these experiments, we are able to better understand the working principles and internal processes of Li-ion batteries and improve their efficiency, reliability, and safety based on this knowledge. However, conducting these experiments poses several challenges, which are described in the paper, along with ways in which they can be partially mitigated.
|
|
|
Interconnection of three-dimensional printing, material science and bone tissue engineering for creating ideal bone scaffolds
Šromová, Veronika
The interconnection of three-dimensional (3D) printing, material science, and bone tissue engineering holds immense promise in the realm of scaffold development for bone repair. This work delves into the intricate interplay between various factors influencing the success hydroxyapatite biomaterials in bone regeneration, including material selection, porosity, structural design, surface modification, and other mechanical characteristics. Our aim is the pursuit of ideal biomaterials possessing both favorable biological responses and mechanical integrity. Fourier transform infrared spectroscopy (FTIR) is used to analyze the chemical structure of the material, particularly the chemical bonds present. Using SEM, we were subsequently able to analyze the microstructure and nanostructure of the 3D printed hydroxyapatite sample.
|
|
|
Novel materials for sensing and biosensing
Jyoti, Jyoti ; Mayorga, Paula (referee) ; Cho, Nam-joon (referee) ; Pumera, Martin (advisor)
Materiály na bázi 2D použité ve 3D tištěných elektrodách a nano/mikromotorech se staly špičkovými technologiemi. Získaly širokou pozornost díky svým výjimečným charakteristikám, které je předurčují pro použití v senzorových a biosenzorových aplikacích. Výzkum nabízí cenné vhledy prostřednictvím systematického výzkumu za účelem podpory pokroku v senzorových technologiích. 3D tištěné elektrody z nanouhlíku eliminují potřebu konvenčních elektrod tím, že poskytují výhody jako snadnou výrobu, rychlou produkci, vynikající přesnost a přizpůsobení tvarů v závislosti na našich požadavcích. V důsledku toho zjištění této práce zdůrazňují univerzálnost 3D tištěných elektrod z nanouhlíku v aplikacích, které zahrnují fenoly, pesticidy a biosensing, zejména detekci DNA. Dále jsme zkoumali aktivní kvantové materiály na bázi mikromotorů pro detekci DNA, stejně jako aplikace pro bezpečnost potravin. Tato technologie příští generace kombinuje atraktivní vlastnosti kvantových materiálů spolu s jejich autonomní pohyblivostí jako mikromotory, což detekci urychluje a nabízí cenově dostupné platformy pro senzoriku a bioanalýzu. Řešením výzev souvisejících s využitím analytu, zejména těch s rychlou akcí a toxicitou, práce zkoumá pokročilé metody detekce, které zahrnují moderní technologie nabízející inovativní řešení. Zjištění přispívají k probíhající evoluci technologií nezbytných pro řešení současných výzev v analytické chemii a bioanalytické chemii.
|
|
|
Evaporation of thin films using intense laser light observed operando in a scanning electron microscope
Boleloucká, Eliška ; Ukropcová, Iveta (referee) ; Nováček, Zdeněk (advisor)
This work focuses on the modification of the sample surface using intense laser light. This is one of the desired features of the new generation of multifunctional SPM probes, which are under development. In the first chapter is introduced the SPM probe itself, which allows correlative measurements. Following section contains the implementation of the intense laser light into the electron microscope chamber, together with the modification made to the detection branch of the microscope. The COMSOL Multiphysics software environment is used to simulate the interaction of the laser light with the sample surface. The results of the simulations of the temperature field in the sample are then compared with the results of the direct interaction of the sample surface with the laser light in the electron microscope chamber.
|
|
|
Utilizing of Electron Microscopy for Nanoparticle Detection in Selected Food
Boriková, Natália ; Hrabalová, Vendula (referee) ; Dzurická, Lucia (advisor)
This bachelor thesis deals with the detection of nanoparticles in selected food products using electron microscopy. Specifically, silver pearls, silver powder and food grade whiteness were selected for this purpose. Nanoparticles themselves can have a negative effect on the human body in high concentrations. They need to meet certain legislative standards. The main focus of this bachelor thesis is how nanoparticles could be detected in food. The theoretical part provides an insight into the properties of nanoparticles, their applications and describes methods for their determination, primarily with an emphasis on electron microscopy. In the practical part, solvents with artificially added nanoparticles were prepared and served as standards. Two samples were prepared from selected foods – with and without the addition of nanoparticles. They were analysed using low-energy electron microscope of LVEM 25E type along with elemental analysis using energy dispersive spectroscopy (EDS). The results provide the compositions of the foodstuffs in question and information on the presence of nanoparticles on their own. This research contributes to a better understanding of their characteristics and safety.
|
|
|
Low energy cements based on clinker phases
Šmeral, Miloslav ; Koplík, Jan (referee) ; Bartoníčková, Eva (advisor)
This thesis deals with low-energy cements and the effect of dopants on their hydration, specifically copper and sulfur. The theoretical part summarizes the general information about clinker minerals, their low-energy/low-carbon alternatives and sustainability in the cement industry. Additionally, possible synthesis of clinker minerals are described. In the experimental part, methods for the preparation of doped tricalcium aluminate and the analysis of the synthesized products are presented. The sulfur doped tricalcium aluminate had the highest hydration heat. On the other hand, copper doped tricalcium aluminate and tricalcium aluminate in combination of these dopants exhibited lower hydration heat. The presence of the dopants also affected the composition of the hydration products.
|
|
|
Development of a method for simultaneous measurement of cathodoluminescence and topography of nanostructures
Vacek, Martin ; Klok, Pavel (referee) ; Nováček, Zdeněk (advisor)
The bachelor thesis focuses on the combined use of SPM and SEM techniques using an optical fiber used to collect cathodoluminescence radiation. The thesis contains of a section summarising the used techniques with more detailed description of the cathodoluminescence phenomenon. Following sections describe the development of the method, including the design and construction of the probe, tuning fork and optical fibre modifications. The results show that the newly developed method is capable of providing accurate and reliable results, thus contributing to the expanded capabilities of nanostructure characterization at the Institute of Physical Engineering.
|
guest ::
