In the present paper, the review of the basic results obtained at the Laboratory of Optical Radiation at High Current Electronics Institute SB RAS during 2007-2009 years is presented. Efficient radiation of Ar_{2}, Kr_{2}, Xe_{2}, KrBr*, KrCl*, XeI*, XeBr*, XeCl*, Cl_{2}* molecules and I atoms was obtained in rare gas or in rare gas-Br_{2} (Cl_{2}, I_{2}) mixtures. Study of radiation parameters and lifetime period of the manufactured barrier discharge excilamps has been performed.
Ultraviolet and visible absorption of some sodium and potassium silicate and cabal glasses containing nickel oxide, ferric oxide or both nickel and ferric oxides together have been investigated. In alkali silicate glasses, nickel ions reveal no ultraviolet absorption bands but they show characteristic visible absorption bands due to octahedral and tetrahedral coordinations while iron ions show weak visible absorption bands which are related to ferric ions mostly in tetrahedral state, especially at high alkali oxide content; also iron ions reveal charge transfer ultraviolet absorption bands which are assigned mostly to ferric ions with few ferrous contributions. The proportion of tetrahedral state increases with the increase in the alkali oxide content for the two transition metal oxides. In cabal glasses, nickel ions tend to exist mostly in octahedral state, while ferric ions exist mostly in octahedral and some in tetrahedral form, all the absorption obtained are attributed to their respective energy levels. The ratio of the different coordinations states are discussed in relation to the glass composition.
Photodiagnosis and photodynamic therapy of non-melanoma skin cancers using delta-aminolevulinic acid/protoporphyrin IX (5-ALA/PpIX) give a combined application with broadest dissemination in the current clinical practice. The problems with using of lasers as light sources are the expenses associated with the operation of these types of installations. This is why we test the capability of cheaper sources - light-emitting diodes at 405 nm for fluorescence excitation of PpIX and 635 nm for photodynamic action initiation. A LED matrix is developed in our laboratory using two types of LEDs and a combined photodiagnosis/photodynamic theory device applicable for clinical practice is built. Geometrically matrix is formed in such way that power density at 635 nm is about 40 mW/cm^2, which allow to reach treatment doses for a 15-20 min irradiation depending of the lesion size in the focus of the system. The therapeutic mode of system developed can be used also with some other photosensitizers from the porphyrins derivatives family.
Human skin contains various types of native fluorophores and absorbers with unique absorption and emission spectra, different quantum efficiency, concentration and spatial distribution within the skin. Autofluorescence spectroscopy is applied as diagnostic tool for cutaneous tumor detection that increases the importance of evaluation of natural existing fluorophores and unification of data for given class of pathologies. In the current study, several excitation sources in the region 337-405 nm are applied, to achieve information about typical autofluorescent properties of normal human skin.
The article presents the concept solution of two main issues of visible light communication systems, i.e. the lack of a cost-effective feedback channel and the handling of high throughput. The concept is based on merging of the multiple input multiple output approach, well-known from radio transmission domain, with using of LEDs in a double role, i.e. both as emitters and detectors of light. The feasibility of the proposal was confirmed by the results of the research, carried out for two-channel system of this type.
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