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Behaviour of varnish composite in various environmental condtions
Kadlec, Michal ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
The diploma thesis is focused on the preparation of test samples of paint-filled micronized mica and analysis of electrical properties of insulating material values in different environmental conditions. For this purpose, it was created five sets of composite paint primers with different ratio of mica. Samples were gradually exposed to the environment relative humidity of 0%, 33%, 55%, 65% and 75%. For each environment with a defined moisture characteristics were observed in samples exposed to the temperature of 20 to 50 ° C. The diploma paper analyzed the influence of the mass implementation of mica in each set of samples and placed on the surface structure of samples.
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Analysis of composite system with different filler ratio
Mydlář, Marek ; Frk, Martin (referee) ; Rozsívalová, Zdenka (advisor)
This master’s thesis applies dielectric relaxation spectroscopy to analyse impact of climatic changes on dielectric properties of composite material samples (TSA 220S varnish combined with 60.030 mica). Experiments aim to analyse effect of mica composite mass ratio (0, 4, 8 and 16 % of mica), relative humidity (0, 33, 55, 65, 75 and 95 %) and temperature (23, 30, 40 and 50 C) on complex permitivity as a function of frequency.
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Preparation and Characterization of Drug Carrier Systems on the Basis of Magnetic Nanoparticles
Chvátalová, Barbora ; Burdíková, Jana (referee) ; Kalina, Michal (advisor)
This bachelor thesis deals with the study of magnetic nanoparticles, optimizing their preparation and stabilization. The nanoparticles with different ratios of Fe2+ and Fe3+ ions were prepared by coprecipitation by variously concentrated sodium hydroxide. Three samples of particles were selected and were further observed. Their stability in Milli-Q water, buffer, polyvinylalcohol, hyaluronic acid and chitosan was studied in function of time using methods of dynamic and electrophoretic light scattering. By UV-VIS spectrometry it was confirmed that the magnetic nanoparticles were actually prepared. Nanoparticles coated with chitosan and hyaluronic acid were then further characterized using FT-IR, XRD and SEM.
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Detection of Localized Surface Plasmons on Metal Nanostructures
Konečná, Andrea ; Dub, Petr (referee) ; Kalousek, Radek (advisor)
This bachelor's thesis deals with theoretical and experimental study of localized surface plasmons excited on metal nanostructures. Analytical calculations were compared to simulations and measurements using assembled apparatus and Fourier-transform infrared spectroscopy (FT-IR) in infrared range. Obtained results were discussed considering both validity of performed approximations and quality of manufactured nanostructures.
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GLORIA and Study of Cataclysmic Variables
Šimon, Vojtěch ; Hudec, René
We report here on the ongoing EU FP7 Project GLORIA (GLObal Robotic-telescopes Intelligent Array) with emphasis on possibility of investigation of cataclysmic variables by users. GLORIA will enable the rst free and open-access network of robotic telescopes in the world. We show several examples of the not often used topics (but suitable for GLORIA) for the studies of activity of cataclysmic variables, e.g. search for outbursts in intermediate polars and the uctuations of/nbrightness in their quiescence, and investigation of the optical counterparts of supersoft X-ray sources.
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Frequency stabilization of DBR diode laser working on 633 nm for lenght metrology and spectroscopy
Pham, Minh Tuan ; Hucl, Václav ; Čížek, Martin ; Mikel, Břetislav ; Hrabina, Jan ; Řeřucha, Šimon ; Lazar, Josef ; Číp, Ondřej
Semiconductor lasers are nowadays very convenient and suitable for many applications in field of human activities. Mainly it is thanks to their small size, low cost and high energy efficiency. This work deals with frequency stabilization of DBR diode laser working on 633 nm and the measurements of its noise properties. For this purpose we have chosen DBR diode EYP-DBR-0633 from Eagleyard Photomic. This particular laser diode in temperature range from 6 degrees celsius to 24 degrees Celsius has a tuning range of 0,86 nm, which correspond to change of 650 GHz in optical frequency domain. In this paper we also present methodology and results for frequency noise properties investigation of this laser with unbalanced Mach-Zhender interferometer and 10 m long fibre spool inserted in reference arm.
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Compact device for fluorescence measurement by optical fiber in microfluidic chip
Ježek, Jan ; Pilát, Zdeněk ; Zemánek, Pavel
In our paper we present a device that combines fluorescence spectroscopy with fiber optics. The device allows high speed detection (in the order of kHz) of the fluorescence signal, which is coming from the sample by an inserted optical fiber, e.g. from a micro-droplet flow in a microfluidic chip, from the liquid flowing in the transparent capillary, etc. The device uses a laser diode at a wavelength suitable for excitation of fluorescence, excitation and emission filters, optics for focusing the laser radiation into the optical fiber, and a highly sensitive fast photodiode for detection of fluorescence.
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SMV-2014-02: Set of absorption cells filled with precisely defined amount of the medium
Lazar, Josef
The research was oriented to technology of optical frequency references - absorption cells - demanded for laser standards frequency stabilization. Iodine absorption cells are commonly operated in regime of saturated vapour - the pressure of gaseous state part of absorbing media is regulated by the temperature control of solid phase part concentrated in cold finger of the cell. The novel approach is based on technology where the cell is filled to precisely defined absorbing media pressure. In this case the cell can be operated in regime where only gaseous iodine is presented, so the cell does not need to be thermostatized by external cooler. We realized a set of cells filled with different pressure levels of media corresponding to saturation temperatures range from -15 to +85 degrees of Celsius. The research also included development of novel techniques for filling the cells above the standard room temperatures.
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SMV-2012-29: Absorption cell for laser interferometry
Lazar, Josef ; Hrabina, Jan
The research included investigation of spectral properties of molecular iodine absorption cell intended for ultra-precise laser interferometer referencing to primary standard of length. The cell was based on fused silica glass material which allowed us to reach ultra-pure absorption environment without negative foreign-gas distortion effects (collisional quenching, frequency stability degradation).
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