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The Role of Ratings in the Development of Business Processes of Russian Banks
In: Vestnik MGIMO-Universiteta: naučnyj recenziruemyj žurnal = MGIMO review of international relations : scientific peer-reviewed journal, Heft 1(22), S. 260-266
ISSN: 2541-9099
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Energy Conversion of X-ray, Ultraviolet and Infrared Radiation in Gd2O3 Crystals Doped with Er3+ Ions
Spectra of photoluminescence (PL) and X-ray excited luminescence (XRL) in region of 1.5-5.0 eV, PL excitation spectra (2.8-5.8 eV), PL decay kinetics were measured in Gd2O3 crystals doped both with Er3+ and Zn2+ ions. Synchrotron radiation (VEPP-3 storage ring, Novosibirsk, Russia) were used for XRL measurements. PL spectra were studied at room temperature and T= 88 K under excitation with energy Eexc: a) in fundamental absorption region (Eexc≥Eg); b) in intracenter excitation region (Eexc
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Comparative assessment of the content of transition metals (Cu, Zn, Mn, Pb, Cd) and radiocesium (137Cs) in pike (Esox lucius) and burbot (Lota lota) of the Yenisei River
In: Сибирский экологический журнал, Band 29, Heft 1, S. 111-121
Testing Performance of Pr3+-doped KLuP2O7 upon UV-, Synchrotron X-Ray and Cathode-Ray Excitation
The luminescent characteristics of the double phosphate KLuP2O7 doped with Pr3+ ions, a promising optical material for scintillator applications, were investigated using various experimental spectroscopic techniques. KLuP2O7:Pr3+ shows Pr3+ emission associated with interconfigurational 4f15d1→4f2 transitions located in the UV range (250–320 nm), intraconfigurational 4f2→4f2 transitions (weak lines in the visible spectral range) and defect-related luminescence. The light output of X-ray or cathode ray excited Pr3+ 4f15d1→4f2 luminescence is found to be nearly independent of temperature in the range of 90–400 K. The output of pulsed cathode luminescence shows thermal quenching above 450 K characterized by an activation energy of about 0.5 eV. Upon excitation with pulsed cathode rays or high-frequency (~8 MHz) X-ray synchrotron radiation, the luminescence decay kinetics of Pr3+ 4f15d1→4f2 transitions are dominated by a decay component with lifetime of about 20 ns. An additional slower decay component with lifetime of 75 ns was observed upon cathode ray excitation and was shown to result from delayed host-to-impurity energy transfer. The latter, in turn, originates from re-trapping of charge carriers at defect-related traps whose presence was demonstrated by thermoluminescence measurements. Parameters of the trapping centers were estimated. Peculiarities of host-to-impurity energy transfer are analysed and discussed. © 2020 Elsevier B.V. ; The work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (through the basic part of the government mandate, Project No. FEUZ-2020-0060), Act 211 Government of the Russian Federation (contract № 02.A03.21.0006 ) and RFMEFI62117X0012 project as well as by Estonian Research Council (project PRG629 ) and Estonian Centre of Excellence in Research "Advanced materials and high-technology devices for sustainable energetics, sensorics and nanoelectronics" TK141 (2014-2020.4.01.15-0011) . E. Trofimva is thankful for support by European ...
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