|
|
Study of concrete properties with nanoparticles
Michnová, Kamila ; Hela, Rudolf (referee) ; Bodnárová, Lenka (advisor)
This diploma thesis discusses the basics of nanotechnology as a science and nanotechnology of concrete. Additionally, it describes carbon nanotubes and the possibilities of their dispersion using high shear mixing and sonication. This thesis further provides findings about ultrasonic dispersion parameters and characteristics of materials with the addition of carbon nanotubes. The experimental of part of this thesis focuses on the possibility of dispersing carbon nanotubes, deals with the issue of incorporating carbon nanotubes into the concrete matrix and describes its effects on the final properties of concrete. It has been observed to which extent the carbon nanotubes may affect selected physico-mechanical properties and durability of concrete.
|
|
|
Electrochemical impedance spectroscopy as a nanostructured bioelectrodes characterization method
Vrbová, Eva ; Urbánková, Kateřina (referee) ; Hrdý, Radim (advisor)
Diploma thesis deals of nanostructured surfaces, nanoparticles and electrochemical characterization methods such as cyclic voltammetry, differential pulse voltammetry and electrochemical impedance spectroscopy. The aim of this thesis is a theoretical research issues of production and characterization nanostructured modified electrodes. The practical part is the production of biomodified nanostructured electrodes by anodi- zation W/Al layers with galvanic deposition of gold or deposition of mercury, a modifi- cation of the electrodes by 11-mercaptoundecanoic acid and by bovine serum albumin (BSA). The thesis includes SEM images of nanostructured electrodes contact angle mea- surements of these electrodes and form an electrical circuit with subsequent simulation waveforms.
|
|
|
Control software for system of post-process nanostructure deposition
Brabec, Luboš ; Sysel, Petr (referee) ; Hubálek, Jaromír (advisor)
This bachelor's thesis deals with problematics of technological processes and techniques for modification of microelectrodes with nanostructures. Furthermore, it describes a device needed for automated providing processes, communication with computer and of controlling system for all functions. These devices communicate through RS-232 and USB interfaces. Developed programmeg control communicates from PC with all devices and it creates interface for user enabling to set parameters of all processes followed by their providing without user supervision.
|
|
|
Nanostructures and Nanosensors
Křečková, Jitka ; Haupt, Jaromír (referee) ; Ellederová, Eva (advisor)
Cílem této bakalářské práce je představit využití nanotechnologie ve snímacích zařízeních, poskytnout základní informace o nanotechnologii, včetně popisu a klasifikace nanostruktur, a zdůraznit možnost vylepšení výkonu senzoru prostřednictvím nanotechnologie. Tato práce se také zabývá využitím nanodrátu jako součástí senzoru s konfigurací unipolárního tranzistoru. Kvantové tečky a jejich využití v optické detekci jsou také zahrnuty v této práci. Výhody i současná omezení nanosenzorů jsou shrnuty v závěru práce.
|
|
|
Study possibilities of nanotechnology in cement composites
Kardošová, Romana ; Bodnárová, Lenka (referee) ; Hela, Rudolf (advisor)
The aim of this paper is to summarize and assess the possibility of using nanoparticles as additives in concrete. These particles have the ability to improve the mechanical and physical properties of cement composites or even gave them brand new ones. Industrial use is hampered by effective incorporation of nanoparticles into the matrix, the health and environmental risks and, last but not least, the financial costs. The experimental part of the thesis deals with the dispersing nanosilica and nanometakaolin particles in aqueous solution and their subsequent integration into the structure of cement mortar.
|
|
|
Research and Development of Modern Emission MEMS Sensors
Pekárek, Jan ; Husák, Miroslav (referee) ; Vlach, Radek (referee) ; Vrba, Radimír (advisor)
The dissertation thesis is focused on research and development of modern emission MEMS sensors. The emission sensor based on the field emission from nanostructured materials represents innovative approach to pressure sensing. The nanostructures serve as electron emitter in an electric field between the cathode and anode in the pressure sensor. This electric field is constant and the change in ambient pressure causes the change of distance between electrodes, thereby the electric field is increasing. This intensity is proportional to the emission from the cathode made of nanostructured material. Changing the distance between the electrodes is caused by the deflection of the deformation element - the membrane, which operates the measured pressure. In the current state of the art an extensive research is carried out to find new nanostructured materials with good emission properties. Four nanostructured materials have been chosen and then experimentally prepared and characterized inside the vacuum chamber. For the simulation of diaphragm bending, the chamber is equipped with linear nano-motion drive SmarAct that enables precise changes of the distance between two electrodes inside the vacuum chamber. The computer model to predict the deformation of diaphragm was prepared in the simulation program CoventorWare. The behavior of diaphragm in a wide range of dimensions of the membrane, its thickness and the applied pressure are possible to predict. The dependencies of the current density on the electric field are plotted from the measured emission characteristics of nanostructured materials and thus characterized nanostructured materials can be compared. The dependencies are further converted by Fowler-Nordheimovy theory on the curve (ln(J/E2) vs. 1/E), whose advantage is linear shape. Basic parameters describing the emission properties of characterized nanostructured materials are deducted. Two methods for vacuum packaging of the sensor electrodes are designed. Anodic bonding technology and encapsulating using glass frit bonding are tested. To evaluate the bonding strength, the bonded substrates are tested for tensile strength.
|
|
|
The use of nanotechnology for ultra-high strength concretes
Šindelek, David ; Bodnárová, Lenka (referee) ; Hela, Rudolf (advisor)
This diploma thesis deals with the concept of use of nanotechnology for cement composites and UHPC. In the theoretical part of this diploma thesis there are theoretical principles described for successful design of high performance concrete and characteristics of main feedstock and its production. Furthermore, there is a focus on nanoparticles, especially the ones with carbon base in the form of carbon nanotubes CNT, in addition to that, graphenes GN that are new on the market, moreover, graphene oxide GO and its application in cement composites to mechanical characteristics and its durability. The first part of the practical part devotes in trying to find out an optimal parameter for ultrasonic mix with a suitable surface active substance of three graphenes. The other two parts of the practical part are about influence of graphenes on mechanical characteristics, cement paste microstructure, and application in the mix of concrete C 35/45 and UHPC
|
|
|
Application of nanofiller in electroinsulating materials
Mohyla, Petr ; Rozsívalová, Zdenka (referee) ; Frk, Martin (advisor)
This project deals with calculation parts of complex permittivity varnish samples which is filled by nanoparticles of metal oxides. Opening of this project deals with theory of dielectric and effects in dielectric, theory of compounds and expressions in composite systems. Following topic is theory of nanoparticles and nanotechnologies and summarize adjusted results about this branch of knowledge. In practical part of work is include method which was use to make varnish samples filled by nanoparticles, prepare to measurement methods and whole results of measurement. In the end of work is analysis influence of filler particles each filler types to dielectric material and results verified mixture mathematical expressions.
|
|
|
Development of a linear stage actuator for UHV STM/AFM
Pavelec, Jiří ; Jiruše, Jaroslav (referee) ; Šikola, Tomáš (advisor)
The aim of this diploma thesis is to develop a linear positioning stage for Ultra High Vacuum (UHV) environment. Simple prototypes of the linear positioning stage were designed and incorporated as part of a multiaxis sample manipulator for a UHV Scanning Tunneling Microscopy / Atomic Force Microscopy (STM/AFM). Different types of position encoders and linear guideways are discussed. Implementation of the homodyne interferometer as an optimization tool for a slip-stick based linear stage is described. Scalar diffraction theory is used to model the diffraction grating optical position encoder behavior.
|
|
|
Theoretical use of nanotechnology for filtration in HVAC systems
Bosák, Jan ; Ell, Jiří (referee) ; Rubina, Aleš (advisor)
Thesis solves problems using the nanotechnology for air filtration in HVAC systems. Main specialization work is air filtration for clean spaces with high classes of purity. For example Hospitals, sophisticated technology service, pharmacy etc. Thesis is devide for three parts. First part contains foundation infromations about theory and making fabrics by nanotechnology. Next I described laws of physics, That were using during the solving filtration´s issues. Goal for second part was making the experiments, which should show abilities and properties nanofilters during the air filtration in real environment HVAC systems. In the end measure part is compare nanofilters with common filters. There is describe nanofiltres behavior and their possibilies during the filtration as well as. In last part I expressed own opinions on air filtration by nanofibers. Opinions were making throught informations, That I found out in the process working on thesis and my experiences in HVAC field. By this facts I did compare for get a better idea. Additionally last part contains summary infomations from previously parts and own vision to development in the future. Goal work isn´t promotion and advertising sorts technologies. Ask is just summary and describe discovered knowledges, considered opinions ensue from measuring, information from the Net and people Who work in nanotechnology field.
|
guest ::
