Browsing Внеуниверситетские публикации ученых БНТУ by Title

Now showing items 42-61 of 4309

    • Competition between electron transfer and energy migration in self-assembled porphyrin triads 

      Zenkevich, E. I.; Willert, A.; Bachilo, S. M.; Rempel, U.; Kilin, D. S.; Shulga, A. M.; Borczyskowski, C. von (2001)
      The photoinduced electron transfer (ET) and the energy migration (EM) processes have been studied in liquid solutions and polymeric (PMMA) films for the triads consisting of the Zn-octaethylporphyrin chemical dimer (the energy and electron donor, D) and dipyridyl substituted tetrapyrrole extra-ligands (porphyrins, chlorin, tetrahydroporphyrin) as the acceptors, A. On the basis ...
      2017-05-26

    • Complexation and interchromophoric interactions in self-organized porphyrin and chlorin triads 

      Chernook, A. V.; Shulga, A. M.; Zenkevich, E. I.; Rempel, U.; Borczyskowski, C. von (1996)
      Spectral properties and equilibrium constants of multimolecular complexes (triads) formed by 2-fold coordination of dipyridyl-substituted free bases of porphyrin, chlorin, or tetrahydroporphyrin with Zn-porphyrin and Zn-chlorin dimers bridged by either of two different spacers between the monomeric entities have been studied in methylcyclohexane at room temperature. The ability ...
      2017-05-18

    • Composite Materials for Steel Cutting and Concrete Crushing 

      Usherenko, Y.; Usherenko, S.; Yazdani, J. (2017)
      The steel based on composite material, created by the stitching of steel matrix by a flow of powder particles. Stitching process implemented in conditions of super deep penetration (SDP) which provides a penetration of the powder particles at speed 1000 m/s on depth up to hundred millimeters. Due to the interaction between the particles and the steel matrix at pulsating pressureabove ...
      2018-03-10

    • Concentration effects in pigment solutions 

      Gurinovich, G. P.; Losev, A. P.; Zenkevich, E. I. (1978)
      Gurinovich, G. P. Concentration effects in pigment solutions / G. P. Gurinovich, A. P. Losev, E. I. Zenkevich // Spectroscopy Letters. – 1978. – Vol. 11, № 7. – P. 493-511.
      2017-05-18

    • Conceptual approach to the development of enterprises of any ownership in modern conditions of economic development 

      Paddziarehina, L. I.; Gainutdinoy, E. M. (ВГТУ, 2016)
      Paddziarehina, L. I. Conceptual approach to the development of enterprises of any ownership in modern conditions of economic development / L. I. Paddziarehina, E. M. Gainutdinoy // Education and science in the XXI century : articles of the International Scientific and Practical Conference, (Витебск, 27 октября 2016 г.) . – Витебск : ВГТУ, 2016. – C. 80-82.
      2019-10-29

    • Constructive Theory of Scalar Characteristic Equations of the Theory of Radiation Transport: II. Algorithms for Finding Solutions and Their Analytic Representations 

      Rogovtsov, N. N. (2015)
      We present methods for finding discrete spectra and derive analytic expressions for the eigenfunctions of scalar characteristic equations of the theory of radiation transport. We obtain new two-term recursion formulas and analytic representations for solutions of infinite tridiagonal systems of linear algebraic equations. We obtain analytic forms of the resolvents of scalar ...
      2017-11-23

    • Continuous-wave and Q-switched operation of a compact, diode-pumped Yb3+:KY(WO4)2 planar waveguide laser 

      Bain, F. M.; Lagatsky, A. A.; Kurilchick, S. V.; Kisel, V. E.; Guretsky, S. A.; Luginets, A. M.; Kalanda, N. A.; Kolesova, I. M.; Kuleshov, N. V.; Sibbett, W.; Brown, C. T. A. (Optical Society of America, 2009)
      A diode-pumped LPE-grown Yb:KYW planar waveguide laser is demonstrated in a microchip monolithic cavity configuration. Output powers as high as 148mW and thresholds as low as 40mW were demonstrated during continuous-wave operation. Pulses of 170ns duration with maximum pulse energy of 44nJ at a 722kHz repetition rate were generated when Q-switched using a semiconductor saturable ...
      2012-01-23

    • Controlling the characteristics of photovoltaic cells based on their own semiconductors 

      Vorobey, R. I.; Gusev, O. K.; Tyavlovsky, K. L.; Svistun, A. I.; Shadurskaya, L. I.; Yarzhembitskaya, N. V.; Kierczynski, K. (Wydawnictwo SIGMA, 2015)
      The features of photovoltaic cells with their own photoconductivity in semiconductors with deep-level multiply-charge impurity have been considered. The use of such structures can significantly extend the dynamic range of sensitivity and gain new functional properties of single-element photoelectric receivers. Photovoltaic converters based on semiconductors with deep-level ...
      2022-07-13

    • Cooperative up-conversion in Eu3+,Yb3+-doped SiO2–PbO–PbF2–CdF2 oxyfluoride glass 

      Loiko, P. A.; Rachkovskaya, G. E.; Zakharevich, G. B.; Kornienko, A. A.; Dunina, E. B.; Yasukevich, A. S.; Yumashev, K. V. (Elsevier, 2014)
      Novel oxy fluoride glass doped with YbF3 and Eu2O3 is synthesized in the SiO2–PbO–PbF2–CdF2 system by melt quenching technique. Its physical properties, as well as the optical absorption of Eu3+ and Yb3+ ions are studied. Spectroscopic properties of Eu3+ ions are modeled within modified Judd–Ofelt theory, yielding absorption oscillator strength, luminescence branching ratios and ...
      2016-01-05

    • Critical phenomena soft modes and negative Poisson’ ratio 

      Nemtsov, V. B.; Shirko, A. V.; Belov, V. V. (БНТУ, 2011)
      The article phenomena, soft modes and negative Poisson’ ratio are considered on bases at statistical theory.
      2012-06-14

    • CRM-системы: работа на стратегическом и операционном уровнях маркетинга 

      Высторопова, Д.; Гончарова, В. В. (Промкомплекс, 2017)
      Высторопова, Д. CRM-системы: работа на стратегическом и операционном уровнях маркетинга / Д. Высторопова, В. В. Гончарова // Маркетинг: идеи и технологии. – 2017. – № 7. – С. 17-22.
      2019-12-24

    • CW and Q-switched diode-pumped laser operation of Yb 3+:NaLa(MoO4)2 

      Mandrik, A. V.; Troshin, A. E.; Kisel, V. E.; Yasukevich, A. S.; Klavsut, G. N.; Kuleshov, N. V.; Pavlyuk, A. A. (Springer, 2005)
      Continuous wave (CW) and Q-switched diode-pumped laser operation of Yb3+:NaLa(MoO4)2 single crystal was to our knowledge, demonstrated for the first time. A CW output power of 220 mW and slope efficiency of 46% were obtained. Q-switched laser operation was achieved with a pulse duration of 60 ns average output power of 70mW and slope efficiency of 22%.
      2016-03-24

    • Damping of a Solution of Linear Autonomous Difference–Differential Systems with Many Delays Using Feedback 

      Metel’skii, A. V.; Urban, O. I.; Khartovskii, V. E. (2015)
      For linear autonomous difference-differential systems with commensurable delays, the problem of damping the solution by using a linear difference-differential controller with a state feed-back is solved. A generalization of these results to linear autonomous difference-differential systems of neutral type with commensurable delays in the case of a continuous solution is proposed. ...
      2017-11-22

    • Deactivation of excited states in nanostructures containing cu-porphyrin subunit 

      Zenkevich, E. I. (Ивановский государственный химико-технологический университет, 2016)
      Here, we present a semi-review of mutual Belarussian-German collaboration in the field of supramolecular chemistry and photophysics of tetrapyrrole compounds of various types: porphyrin chemical dimers, self-organized multiporphyrin complexes, ordered aggregates of photosynthetic pigments and nanoassemblies based on semiconductor CdSe/ZnS quantum dots and porphyrins. A special ...
      2020-11-11

    • The design and composition of expansion joints on big-span bridges with intensive heavy-duty traffic 

      Busel, A.; Krotau, R. (2016)
      In the Republic of Belarus the roads with a high intensity of transport most widely employ expansion joints with rubber and steel compensators fastened to the reinforced concrete base with embedded therein studs. While operated expansion joints are exposed to various kinds of operational and climatic impacts causing their damage. Expansion joints destruction results in a sharp ...
      2018-03-10

    • Development of the theory of computation of pivotally-connected beams on an elastic foundation taking into account their physical nonlinearity 

      Bosakov, S. V.; Kozunova, O. (Колорград, 2019)
      This work presents a brief review of the literature on the theory and technique of computation of pivotally-connected structures on a linearly-elastic foundation. The authors refer to the works of B.G.Korenev, G.Ya.Popov, I.A.Simvulidi, R.V.Serebryany and A.G.Yuryev, in which investigations for calculating the pivotally-connected beams and slabs on an elastic foundation are ...
      2020-10-08

    • Die Stellung Weißrusslands in der Zollunion 

      Brovka, G. M. (Verlag Recht und Wirtschaft GmbH, 2011)
      Brovka, G. M. Die Stellung Weißrusslands in der Zollunion / G. M. Brovka // Rechtsfragen der Eurasischen Zollunion: Tagungsband zum 15. Munsteraner Aubenwirtschaftsrechtstag 2010 / hrsg. Dirk Ehlers, Hans-Michael Wolffgang, Ulrich Jan Schroder. – Frankfurt am Main: Verlag Recht und Wirtschaft GmbH, 2011. – S. 75-91.
      2019-04-10

    • Diode-pumped passively mode-locked Er,Yb:YAl3(BO3)4laser at 1.5-1.6 μm 

      Lagatsky, A. A.; Kisel, V. E.; Troshin, A. E.; Tolstik, N. A.; Kuleshov, N. V.; Leonyuk, N. I.; Zhukov, A. E.; Rafailov, E. U.; Sibbett, W. (2008)
      We report the first demonstration to our knowledge of passive mode locking in a diode-pumped Er3+ and Yb3+ codoped YAl3(BO3)4 laser operating in the 1.5-1.6 μm spectral region. Low-loss GaInNAs quantum-well semiconductor saturable absorber mirrors are used for the initiation and stabilization of the ultrashort-pulse generation. Pulses as short as 4.8 ps were generated at 1530 nm ...
      2012-01-23

    • Diode-pumped passively Q-switched self-frequency-doubled ND:CNGS laser 

      Zhang, X.; Zhou, Y.; Yasukevich, A. S.; Loiko, P. A.; Mateos, X.; Xu, X.; Guo, S.; Wang, Z. (Optical Society of America, 2017)
      With Cr4+:YAG as a saturable absorber, a passively Q-switched self-frequencydoubled (SFD) laser based on a trigonal Nd:Ca3NbGa3Si2O14 (Nd:CNGS) silicate crystal was demonstrated for the first time. The maximum average output power at 532 nm was 16.2 mW, and the corresponding pulse repetition frequency, single pulse energy, pulse duration and peak power were 2.25 kHz, 7.2 μJ, 13.7 ...
      2023-12-15

    • Directed energy transfer due to orientational broadenning of energy levels in photosynthetic pigment solutions 

      Rubinov, A. N.; Zenkevich, E. I.; Nemkovich, N. A.; Tomin, V. I. (1982)
      The directed non-radiative energy transfer through monomeric molecules of chlorophyll “a” and pheophytin “a” at high concentrations (c ~ 10⁻²) in a rigid matrix of polyvinylbutyral has been found by using the nanosecond laser spectrofluorimeter. The phenomenon is caused by orientational broadening of pigment molecular spectra owing to its interaction with a solvent. The observed ...
      2017-05-18