Now showing items 125-144 of 1050

    • Rzeczoznawstwo w Bialorusi 

      Trifonov, N. J. (2004)
      Trifonow, N. J. Rzeczoznawstwo w Bialorusi / N. J. Trifonow // XIII Krajowa konferencja rzeczoznawcow majątkowych "Refleksje nad zawodem rzeczoznawcy majatkowego w Unii Europejskiej - nadzieje i zagrozenia", 9-11 wrzesnia 2004 r. : Materialy konferencyjne. – Rzeszow: 2004. – P. 165-182.
      2014-01-27
    • Sci-Hub как зеркало комплектования научных и образовательных организаций онлайн-ресурсами 

      Шварцман, М. Е.; Лебедев, В. В.; Скалабан, А. В. (2015)
      Введение: для выбора оптимальной стратегии комплектования научных и образовательных учреждений онлайн-ресурсами необходимо использовать новые подходы. В качестве одного из них российские ученые могут выбрать сайт Sci-Hub как наиболее доступный в настоящее время ресурс для получения информации о зарубежных публикациях. Целью исследования является поиск дополнительных критериев ...
      2017-12-07
    • Self-assembled nanoscale photomimetic models: structure and related dynamics 

      Zenkevich, E. I.; Borczyskowski, C. von; Shulga, A. M.; Bachilo, S. M.; Rempel, U.; Willert, A. (2002)
      Using static and time-resolved measurements, dynamics of non-radiative relaxation processes have been studied in self-assembled porphyrin triads of various geometry, containing the main biomimetic components, Zn–porphyrin dimers, free-base extra-ligands (porphyrin, chlorin or tetrahydroporphyrin), and electron acceptors A (quinone or pyromellitimide). The strong quenching of the ...
      2017-05-26
    • Self-organization principles in the formation of multiporphyrin complexes and “semiconductor quantum dot-porphyrin” nanoassemblies 

      Zenkevich, E. I.; Borczyskowski, C. von (2014)
      In this paper, we review several aspects of molecular recognition (based on non-covalent binding interactions) occurring between meso-pyridyl substituted tetrapyrrole extra-ligands and chemical dimers of tetrapyrrolic macrocycles containing central Zn ions and spacers of various nature and flexibility. Experimental results obtained by us earlier are analyzed using a novel approach ...
      2017-05-27
    • Semiconductor A3B5 nanostructures for infrared femtosecond lasers 

      Rubtsova, N. N.; Kochubei, A. A.; Kovalyov, A. A.; Preobrazhenskii, V. V.; Putyato, M. A.; Semyagin, B. R.; Shamirzaev, T. S.; Borisov, G. M.; Kisel, V. E.; Kuleshov, N. V.; Kuril'chik, S. V.; Buganov, O. V.; Tikhomirov, S. A. (Institute of Physics, 2013)
      Two techniques were suggested and tested for the recovery time shortening of saturable absorbers on a base of A3B5 compounds including quantum wells. The first one, proposed by authors, is the sample post-growth treatment by UV laser radiation; it implied generation of point defects, which, in its turn, led to electron-hole recombination acceleration and to recovery time shortening ...
      2016-05-11
    • The Shape of the Magnetic Fluid Surface above a Magnetizable Sphere in a Uniform Magnetic Field 

      Bashtovoi, V. G.; Motsar, A. A.; Naletova, V. A.; Reks, A. G. (2015)
      The shape of the free surface of a magnetic fluid above a spherical ferromagnetic body immersed in it in a uniform magnetic field is investigated experimentally. The effect of the direction and magnitude of the magnetic field on the deformation characteristics of the free surface of the magnetic fluid with various magnetic properties and geometrical parameters is established.
      2017-11-23
    • Size-Dependent Non-FRET Photoluminescence Quenching in Nanocomposites Based on Semiconductor Quantum Dots CdSe/ZnS and Functionalized Porphyrin Ligands 

      Zenkevich, E. I.; Blaudeck, T.; Milekhin, A.; Borczyskowski, C. von (2011)
      We review recent experimental work to utilize the size dependence of the luminescence quenching of colloidal semiconductor quantum dots induced by functionalized porphyrin molecules attached to the surface to describe a photoluminescence (PL) quenching process which is different from usual models of charge transfer (CT) or Foerster resonant energy transfer (FRET). Steady-state ...
      2017-05-27
    • Some aspects of sherardizing implementation during anti-corrosion protection of heat-treated metal parts 

      Konstantinov, V. M.; Buloichyk, I. A. (2015)
      The article reveals the peculiarities of obtaining Zn anticorrosive diffusion layers on heat-treated metal parts using sherardizing method. It is shown that sherardizing processes can be successfully used as a final heat treatment operation for some metal parts after hardening in a temperature gap between 350-700 degrees C. 380-450 degrees C. are the most efficient temperatures ...
      2018-03-15
    • Some principles of teaching translation 

      Перепечко, Н. Н. (АГУ, 2013)
      Перепечко, Н. Н. Some principles of teaching translation / Н. Н. Перепечко // Межкультурная коммуникация и СМИ : материалы IV Международной научно-практической конференции, Барнаул, 15 июня 2013 г. – 2013. – С. 71-74.
      2014-03-31
    • Spectral Рeculiarities of NH-Tautomerism in Isocycle-Containing Porphyrins and their Covalently Linked Dimers 

      Zenkevich, E. I.; Shulga, A. M.; Chernook, A. V.; Gurinovich, G. P. (1984)
      It has been found experimentally that a whole class of isocycle-containing porphyrins, including synthetic and natural objects and their covalently linked dimers, shows NH-tautomerism which manifests itself in isotropic solutions in normal electronic spectra both at 77 K and higher temperatures (up to 500 K).
      2017-05-18
    • Spectroscopic and photoluminescence characterization of Eu 3+-doped monoclinic KY(WO4)2 crystal 

      Loiko, P. A.; Dashkevich, V. I.; Bagaev, S. N.; Orlovich, V. A.; Yasukevich, A. S.; Yumashev, K. V.; Kuleshov, N. V.; Dunina, E. B.; Kornienko, A. A.; Vatnik, S. M.; Pavlyuk, A. A. (Elsevier, 2014)
      Monoclinic 2 at% Eu-doped KY(WO4)2 is grown by top-seeded solution growth method. Polarizationresolved absorption and stimulated-emission cross-section spectra are determined for this crystal. Spectroscopic properties of Eu:KY(WO4)2 are modeled within conventional Judd–Ofelt theory, as well as theory of f–f transition intensities for systems with anomalously strong configuration ...
      2016-02-08
    • Spectroscopy and femtosecond laser performance of Yb3+:YAlO3 crystal 

      Kisel, V. E.; Kurilchik, S. V.; Yasukevich, A. S.; Grigoriev, S. V.; Smirnova, S. A.; Kuleshov, N. V. (Optical Society of America, 2008)
      We report what we believe to be the first demonstration of cw and passively mode-locked Yb3+:YAlO3(Yb:YAP) laser operation under diode pumping. Spectroscopic properties of a 0.6 at.%Yb3+-doped YAP single crystal were investigated. Output power up to 1.2 W with slope efficiency of 64.5% in the cw regime and 225 fs pulse duration with average power of 0.8 W from a mode-locked Yb:YAP ...
      2012-01-23
    • Spectroscopy of interchromophoric interactions in self-organized porphyrin and chlorin complexes 

      Zenkevich, E. I.; Shulga, A. M.; Chernook, A. V.; Rempel, U.; Borczyskowski, C. von (1995)
      Spectral-luminescent properties of multimolecular complexes (triads and pentads, complexation constants range from 5∙10⁶ to 5∙10⁷ M⁻¹) formed by two-fold coordination of dipyridyl and tetra-pyridyl substituted porphyrin or related molecules with Zn-porphyrin and Zn-chlorin dimers having various spacers between macrocycles (-CH₂-CH₂- or phenyl ring) have been studied in methylcyclohexane ...
      2017-05-18
    • Spectroscopy of tetragonal Eu:NaGd(WO4)2 crystal 

      Loiko, P. A.; Vilejshikova, E. V.; Mateos, X.; Serres, J. M.; Dashkevich, V. I.; Orlovich, V. A.; Yasukevich, A. S.; Kuleshov, N. V.; Yumashev, K. V.; Grigoriev, S. V.; Vatnik, S. M.; Bagaev, S. N.; Pavlyuk, A. A. (2016)
      We report on growth and detailed spectroscopic study of Eu3ю-doped tetragonal sodium gadolinium double tungstate, Eu:NaGd(WO4)2, a new promising crystal for deep-red lasers. Large-volume crystal doped with 4.9 at.% Eu is grown by Czochralski method along the [001] crystallographic direction. Absorption of Eu3ю ions is studied at room temperature (RT) and at 6 K. For the absorption ...
      2017-11-18
    • Statics of Magnetic Fluid Drop with Compound Magnetic Core in a Wedge-Shaped Channel 

      Bashtovoi, V. G.; Klimovich, C.; Motsar, A.; Reks, A. G.; Ryapolov, P. A.; Storozhenko, A.; Shabanova, I. (Sumy State University, 2013)
      A behavior of magnetic fluid drop with compound magnetic core in a wedge-shaped channel was studied experimentally. The study examines influence of magnetic fluid properties, its volume and magnetic field on statics of the system compound magnet – magnetic fluid drop in wedge-shaped channel. The possibility to change the static conditions of such system by altering magnetic field ...
      2016-03-29
    • Steric interactions influence on electron transfer efficiency in meso-nitrophenylporphyrins and their chemical dimers 

      Knyukshto, V. N.; Zenkevich, E. I.; Sagun, E. I.; Shulga, A. M.; Starukhin, D. A.; Bachilo, S. M. (2001)
      Steric interactions upon mono- and di-meso-phenyl substitution in octaethylporphyrins (OEP) and their chemical dimers with the phenyl spacer manifests itself in the dramatical T₁-state lifetimes shortening at 293 K (from ms down to μs in degassed toluene solutions) without any influence on spectral-kinetic parameters of S₀- and S₁-states. This effect is explained by non-planar ...
      2017-05-26
    • Stokes and anti-Stokes luminescence from cubic elpasolite Cs2NaYF6 crystals doped with Er3+and Yb3+ ions 

      Loiko, P. A.; Khaidukov, N. M.; Mendez-Ramos, J.; Vilejshikova, E. V.; Skoptsov, N. A.; Yumashev, K. V. (Elsevier, 2016)
      Er3þ and Yb3þ doped cubic elpasolite Cs2NaYF6 crystals including stoichiometric compositions Cs2NaErF6 and Cs2NaYbF6 have been synthesized under hydrothermal conditions. Absorption, stimulated-emission and gain cross-sections spectra have been determined for the 2F5/2-2F7/2 (Yb3þ) and 4I13/2-4I15/2 (Er3þ) transitions at room-temperature. The maximum σSE values are 1.8 10 21 cm2 ...
      2016-05-12
    • Structural Dynamics and Relaxation Processes with Participation of Excited Singlet and Triplet States in Sterically Hindered Porphyrins and Their Chemical Dimers 

      Zenkevich, E. I. (2014)
      Paper presents an overview of mutual Belarussian-Russian collaboration in the field of sterically hindered porphyrins compared with the relevant literature data. Typically, the conformational dynamics of a non-planar tetrapyrrole macrocycle at 295 K manifests itself in bathochromic absorption and fluorescence shifts (∆ν ~ 1100 cm⁻¹), the increase of the Stokes shift (∆νₛ ~ 900 ...
      2017-05-27
    • Structure and nonlinear optical properties of novel transparent glass-ceramics based on Co2+:ZnO nanocrystals 

      Loiko, P. A.; Dymshits, O. S.; Vitkin, V. V.; Skoptsov, N. A.; Zhilin, A. A.; Shemchuk, D. V.; Tsenter, M. Ya.; Bogdanov, K. V.; Malyarevich, A. M.; Glazunov, I. V.; Mateos, X.; Yumashev, K. V. (2016)
      Transparent glass-ceramics (GCs) based on Co2+:ZnO nanocrystals (mean diameter, 11 nm) are synthesized on the basis of cobalt-doped glasses of the K2O–ZnO–Al2O3–SiO2 system. For these GCs, the absorption band related to the 4A2(4F) → 4T1(4F) transition of Co2+ ions in tetrahedral sites spans until ~1.73 μm. Saturation of the absorption is demonstrated at 1.54 μm, with a saturation ...
      2017-11-18
    • Structure-phase condition and tribological properties of coatings based on self-fluxing nickel alloy PG-12N-01 after laser surfacing 

      Devoino, O. G.; Kardapolava, M. A.; Lutsko, N. I.; Feldshtein, E. E. (Kluwer Academic/Plenum Publishers, 2017)
      Some parameters of laser surfacing of self-fluxing nickel alloy PG-12N-01 are considered. Different structures containing a low-melting -Ni – Ni3B eutectic and a -Ni – Cr3C2 eutectic that crystallizes at a higher temperature and forms the strength skeleton of the coating may form depending on the rate of the surfacing. The effect of the rate of the surfacing on the wear resistance ...
      2022-08-09