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Information × Registration Number 0209U006328, 0106U003133 , R & D reports Title Complex studying of secondary-emission processes and development of diagnostics of multicomponent systems, in particular, biological popup.stage_title Head Bobkov Valentin Vasilievich, Registration Date 04-02-2009 Organization Kharkov national university named after V.N. Karazin popup.description2 The object of researches - a number of biological structures including glycerol solutions of organic dyes; tablet targets and targets as water (or alcoholic) solutions of organic dyes deposited on the surface of porous graphite; biological objects prepared by wet ashing, nondoping BGO (Bi4Ge3O12) single crystals. The purpose of work - getting the information about the main parameters of IPE (spectral composition, quantum yield and spatial distribution of radiation of sputtered excited particles) to clear up processes of excited particles formation at an ion bombardment of organic objects; studying of mechanism of luminescence and low temperature anomalies in light reflection in BGO monocrystals.Methods of research - optical spectral analysis of excited particles radiation; photoluminescent and spectral analysis; the method of photo-stimulated current; temperature dependences of intensities of photoluminescence and light reflection; optical light transmission; angle dependences of dispersion of light.Sample of measured complex were done and the investigations of the main parameters of the ion-photon emission during the Ar+ ions bombardment of a number of biological structures and biological objects were provided. On the base of obtained data mechanisms leading to flying-off of excited particles at ion irradiation of organic objects, organic dyes in particular, were cleared. The program of processing of data of analytical measurements of macro- and micro additions was developed. It was concluded that the determination of macro- and micro additions in biological objects of various nature by the ion-photon spectroscopy based on the analysis of IPE main parameters was possible. Photoluminescence and photo-stimulated current (PhSC) of unalloyed monocrystals Bi4Ge3O12 in the range 90 ё 500 К were studied. It was established that at the light action in the range of long-wave edge of characteristic absorption excitons of energies 5.39; 5.17; 4.7; 4.4 eV were formed. As exciton glow was absent it was supposed theresonant mechanism of transferring of excitation energy from excitons allocated in the nearest surroundings of Bi3+ ions. The results showing the relation of PhSC with thermal dissociation of excitons and luminescence absorption were got. The temperature quenching of photoluminescence was related with excitons dissociation. Temperature dependences of light reflection, transmission and scattering in the range of BGO monocrystals transparency were studied. Temperature hysteresis of light reflection in the range 90 ё350 К was set. This hysteresis apparently was caused by surface phase transitions. The results can be used in the determination of main mechanisms of medium energy ions interaction with various substances and the development of united theory of this interaction; at the analysis of surface and bulk compositions of substances. Product Description popup.authors popup.nrat_date 2020-04-02 Close