National Repository of Grey Literature 690 records found  1 - 10nextend  jump to record: Search took 0.18 seconds. 

Determination of Optical Properties of Surfaces for Use in Cultural Heritage Protection
Kocour, Vladimír ; Bryscejn, Jan ; Vrba, David ; Valach, Jaroslav
In this paper we would like to present a simple method of surface reflectance measurement, then to discuss relation between reflectance and surface appearance and what it indicates in the context of shape reconstruction and surface protection.


Depozice a charakterizace nanostrukturních diamantů podobných uhlíkových vrstev obsahujících oxid křemíku
Buršíková, V. ; Zajíčková, L. ; Franta, D. ; Janča, J. ; Buršík, Jiří ; Klapetek, P. ; Bláhová, O. ; Peřina, V. ; Navrátil, V.
The aim present work was to deposit and study nanostructured diamond-like carbon coatings with silicon-oxide content on different substrate materials.The variation in SiOx content enabled to minimize the intrinsic compressive stress in coatings.The influence of the coating/substrate interface properties on the results of the indentation tests and its dependence on the coating thickness was studied.Complex analysis of the maesured coating/substrate response was done and the existing models for substrate influence were tested.

Zlepšení fotoluminescenčních vlastností pomocí autoorganizace blokových kopolymerů
Pavlačková, Petra ; Křenek, R. ; Cimrová, Věra ; Výprachtický, Drahomír ; Stamm, M.
We report on enhancement of photoluminescence of conjugated homopolymers based on poly(p-phenylene) in blends with poly(styrene-block-4-vinylpyridine) copolymer (BC). Using self-organization of BC we may avoid aggregation of the homopolymers. We have got nanostructured films of the blends depending on type of the homopolymer. Enhancement of photoluminescence is also observed.

Physical properties of InP epitaxial layers prepared with dysprosium admixture
Grym, Jan ; Procházková, Olga
Physical properties of commonly prepared InP layers grown by LPE technique and those grown from Dy treated melt are compared. The layers were examined by SEM, low temperature PL spectroscopy, C-V measurements and temperature dependent Hall effect. Structural, electrical and optical properties of InP layers exhibit a significant dependence on the presence of Dy and its concentration in the melt. When increasing the concentration of Dy the reversal of electrical conductivity occurs.

Influence of rare-earth elements on InP-based semiconductor structures for radiation detectors
Grym, Jan ; Procházková, Olga
Preparation and characterization of InP epitaxial layers with Tb admixture in the growth melt is reported. Structural, electrical and optical properties of InP layers exhibit a signaficant dependence on the presence of Tb and its concentration in the melt. When increasing the concentration of Tb in the growth melt the reversal of electrical conductivity occurs.

Microstructure optical fibres
Kaňka, Jiří ; Honzátko, Pavel ; Matějec, Vlastimil ; Kašík, Ivan ; Martan, Tomáš
A review of microstructure optical fibers, their use and methods of preparation is presented. Two classes of microstructure optical fibers in accordance with wave guiding mechanism are introduced. Unique dispersion properties and their structure dependence are discussed. Highly nonliner fibers, large mode area fibers and highly birefringent fibers are reported. Finally, the research carried out IREE Prague is summarized.

Special glasses based on TeO.sub.2./sub. and Pb.sup.2+./sup. systems:preparation and characterisation
Pedlíková, Jitka ; Ležal, Dmitrij ; Zavadil, Jiří
Samples of heavy metal oxide glass system of /TeO.sub.2./sub./.sub.60./sub. . /PbCl.sub.2./sub./.sub.40-x./sub. . /PbF.sub.2./sub..sub.x./sub. where x falls in <0;40>, were prepared and characterised by absorption and photoluminescence spectroscopy. The role of F to Cl subtitution on optical and luminescence properties has been investigated. Selected samples were doped by Er using metal, chloride and oxide precursors. Photoluminescence spectra have been measured in wide temperature range /4-300 K/.

Study of Properties of Metallic Thin Films and Nanostructures Using Scanning Probe Microscopy
Doupal, Antonín ; Fejfar, Antonín (referee) ; Kalousek, Radek (advisor)
This diploma thesis is focused on investigation of metallic thin films and nanostructures using scanning probe microscopy. Magnetic properties of these objects are studied by magnetic force microscopy, which is modification of scanning probe microscopy. In the theoretical part basic principles of scanning probe microscopy and magnetic force microscopy are summarized, and also principle of creation of magnetic domains and some special properties of ferromagnetic and antiferromagnetic materials. Further, two techniques of fabricating nanostructures are described. Experimental part is focused on imaging and simulating of magnetic domains. Further, exchange bias is revealed. This phenomenon is present in systems composed from ferromagnetic and antiferromagnetic materials. One part of this diploma thesis is also focused on discussion of problems with magnetic force microscopy.

Localized Surface Plasmons: Principles and Application
Kvapil, Michal ; Schmidt, Eduard (referee) ; Šikola, Tomáš (advisor)
The diploma thesis deals with plasmonic nanostructures for visible eventually near-infrared region of electromagnetic spectrum. At first, there are discussed basic terms which are necessary for description of plasmonic nanostructures and their properties. Then the resonant properties of gold nanoantennas on a fused silica substrate and in proximity of nanocrystalline diamond are addressed. FDTD simulations are used for an assesment of resonant properties and local electric field enhancement of these nanostructures. Possible manufacturing methods of the antennas and techniques for the measurement of their properties are mentioned at the end of the thesis.