Search Results (28)
Magnetically oriented films of barium ferrite
This work had three aims. In the first part the influences of the sizes of the particles of barium ferrite (BaM) and their magnetic properties on the stability of the suspension were investigated. In second part the deposits were prepared by electrophoretic deposition (EFN) and the influence of particle size, …
Phase slip phenomena and vortex dynamics in mesoscopic superconductors
We investigate the dynamics in one-dimensional (1D) and two dimensional (2D) mesoscopic superconductors in an external magnetic field using the time-dependent Ginzburg-Landau equations. We analyze the different transitions between metastable states and describe the creation of topological defects that occur as the phase of the Ginzburg-Landau order parameter makes finite …
Radio wave propagation in special environments
In this doctoral thesis, radio signal propagation in special environments is discussed. The primary focus is on the development of a path loss model for radio signal propagation in long road tunnels and underground passageways, which allows a rather precise calculation of radio signal path loss and, consequently, a quick …
Microstructural investigations of rare-earth transition-metal-based magnetocaloric materials for near-room-temperature applications
Magnetocaloric materials are promising materials for magnetic refrigerators which would substitute present compressor refrigerators. They work on the principle of the magnetocaloric effect (MCE), where the magnetocaloric material increases its temperature when exposed to an external magnetic field. These new type of refrigerators are energetically more efficient and environmentally friendly. …
Functionalization of Magnetic Nanoparticles
In my doctoral dissertation, I primarily devoted my attention to the modifying surface properties of superparamagnetic maghemite nanoparticles. Superparamagnetic maghemite nanoparticles were synthesized using co-precipitation method from an aqueous solution of Fe (II) and Fe (III) ions. The size of the nanoparticles was controlled with aging time at pH = …
NMR Study of Photoisomerization in Bulk and Confined Liquid Crystals
Deuteron nuclear magnetic resonance was used to study the phase separation behavior of photoisomerizable liquid crystal diheptylazobenzene (7AB). Under UV illumination, the elongated trans molecules are converted to boomerang shaped cis form, creating a binary trans-7AB and cis-7AB mixture. It was demonstrated that the concentration of both components can be …
Hydrogen absorption in Ti-Zr-Ni alloys
Our research focused on the formation of Ti40Zr40-xNi20Cux (x=3, 5), Ti45Zr38-xNi17Cux (x=3, 5), Ti53Zr27-xNi20Cux (x=3, 5) and Ti58Zr24-xNi18Cux (x=3, 5) icosahedral (i-phase) quasicrystals by three different techniques and their subsequent characterization and high-pressure hydrogenation. The quasicrystals of this system are thermodynamically stable and they have a relatively good affinity for …
Development of an alternative approach to membrane protein structure determination based on the analysis of local rotational conformational spaces
The problem of structure determination of membrane proteins is addressed with a new combination of site-directed spin labelling (SDSL) electron paramagnetic resonance (EPR) spectroscopy and structure modelling of a protein and its conformational spaces. This new approach is aimed at structural characterization of membrane proteins and intrinsically disordered proteins. In …