Podbolotov K.B.,Belarusian National Technical University
Refractories and Industrial Ceramics | Year: 2017
Results are provided for a study of porous ceramic materials prepared in the course of chemical and exothermic reactions based on a system containing secondary resources (chamotte scrap, mullite-containing waste, aluminum smelting slag), aluminium phosphate binder, aluminum refractory clay, and various additives. Temperature dependences are established for heat capacity and thermal conductivity in the range 30 – 1000°C for the material obtained. It is shown that the optimum overall aluminum and slag content in a mixture for preparing porous materials is 10 – 20%. It is established that addition of magnesite and chrome-magnesite, and also ammonium dihydrophosphate, makes it possible to control density and strength of the materials obtained. © 2017 Springer Science+Business Media New York
News Article | April 18, 2016
A team of scientists at Lomonosov Moscow State University and the Belarusian National Technical University has created a unique laser. It's a compact light source with wavelengths harmless to the human eye. The device can be used in medicine, communications systems and also in research. The works are published in Journal of Crystal Growth and Optics Letters.
Agency: European Commission | Branch: FP7 | Program: CSA | Phase: INFRA-2007-1.2.3;INFRA-2007-1.2-03 | Award Amount: 3.34M | Year: 2008
The Baltic Grid Second Phase (BalticGrid-II) project is designed to increase the impact, adoption and reach, and to further improve the support of services and users of the recently created e-Infrastructure in the Baltic States. This will be achieved by an extension of the BalticGrid infrastructure to Belarus; interoperation of the gLite-based infrastructure with UNICORE and ARC based Grid resources in the region; identifying and addressing the specific needs of new scientific communities such as nano-science and engineering sciences; and by establishing new Grid services for linguistic research, Baltic Sea environmental research, data mining tools for communication modelling and bioinformatics. The e-Infrastructure, based on the successful BalticGrid project, will be fully interoperable with the pan-European e-Infrastructures established by EGEE, EGEE associated projects, and the planned EGI, with the goal of a sustained e-Infrastructure in the Baltic Region. The present BalticGrid e-Infrastructure of 26 clusters in five countries is envisaged to grow, both in capacity and capability of its computing resources. The consortium is composed of 13 leading institutions in seven countries, with 7 institutions in Estonia, Latvia and Lithuania, 2 in Belarus, 2 in Poland, and one each in Sweden and Switzerland. The overall vision is to support and stimulate scientists and services used in the Baltic region to conveniently access critical networked resources both within Europe and beyond, and thereby enable the formation of effective research collaborations.
Romanczukiewicz T.,Jagiellonian University |
Shnir Y.,Durham University |
Shnir Y.,Belarusian National Technical University
Physical Review Letters | Year: 2010
We present a numerical study of the process of production of kink-antikink pairs in the collision of particlelike states in the one-dimensional 1/4 model. It is shown that there are 3 steps in the process: The first step is to excite the oscillon intermediate state in the particle collision, the second step is a resonance excitation of the oscillon by the incoming perturbations, and, finally, the soliton-antisoliton pair can be created from the resonantly excited oscillon. It is shown that the process depends fractally on the amplitude of the perturbations and the number of perturbations. We also present the effective collective coordinate model for this process.
Agency: European Commission | Branch: FP7 | Program: CSA-SA | Phase: INCO.2010-6.1 | Award Amount: 422.45K | Year: 2010
The project aims at reinforcing RTD and cooperation capacities of the Institute for Nuclear Problems of Belarusian State University in the area of applied nanoelectromagnetics. This new research discipline comprising the classical electrodynamics of microwaves and present-day concepts of condensed matter physics is covered by the FP7 Theme 4 Nanosciences, Nanotechnologies, Materials and new Production Technologies NMP. INP BSU is the founder and leading research center in Belarus in this area. Within the project a set of complementary networking and training activities is foreseen with a strong involvement of already existing and new partners from EU member states and associated countries. Besides, based on research results and their applications in material sciences and medicine, and also taking in consideration the emerging socio-economic needs in Belarus and EU, a strategy of the INP BSU further development will be proposed. All together, the activities will support national RTD in applied nanoelectromagnetics, contribute to young researchers career development, intensify information and experience exchange between Belarus and EU teams thus contributing to creation of the European research network in applied nanoelectromagnetics, as far as increase visibility of INP BSU in the European Research Area and its participation in the FP7. Also, the strategy developed for INP BSU will be proposed and disseminated as a model for the integration of the other Belarus teams into European Research Area.
Pustovalov V.K.,Belarusian National Technical University
Laser Physics | Year: 2011
Absorption, electron-phonon coupling and heating of nanoparticles (NPs) under action of short laser pulses on NPs and their cooling after the end of laser action usually has nonlinear character. Nonlinear electron-phonon coupling under action of pico- and femtosecond pulses on metal NPs depends on electron and lattice parameters. Optical (absorption, scattering, extinction) and thermo-physical (coefficient of thermal conductivity, heat capacity, etc.) parameters of different materials of NPs (metals, oxides, semiconductors, etc.) and environments (water, liquids, dielectrics, etc.) depend on temperature and determine nonlinear dynamics of NPs heating and cooling. It is very important to take into account the temperature dependence of optical and thermophysical parameters of NPs and surrounding media under investigation of absorption of laser radiation, electron-phonon coupling, nanoparticle (NP) heating, heat transfer and its cooling after the end of laser pulse action. Theoretical modeling of the processes of laser-NP interaction taking into account temperature dependences of parameters of NPs and environments was carried out. Influence of temperature dependences of these parameters on values and dynamics of the processes is determined. © 2011 Pleiades Publishing, Ltd.
Zenkevich E.I.,Belarusian National Technical University
Macroheterocycles | Year: 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 (Δv ~1100 cm-1), the increase of the Stokes shift (Δmleso-phenyl-substituted octaarylporphyrins with increasing numbS ~900 cm-1), broadened emission and the fluorescence strong quenching. Nevertheless, the T1 states dynamics upon steric interactions and porphyrin non-planarity remained to be not studied yet. We found for the first time that mono- and di-meso-phenyl substitution in octaethylporphyrins led to a drastic shortening of T1 decays (~1.5 ms → 2-5 μs) in deaerated solutions at 295 K without considerable influence on spectral-kinetic parameters of singlet states. These effects have been systematically studied for porphyrins and their chemical dimers with a controllable structure of meso-phenyl substituents as well as for meso-phenyl-substituted octaarylporphyrins with increasing number (n=1÷4) of meso-phenyl rings. In some cases, quantum-chemical calculations have been used to explain experimental findings. Paper cont ains also some recent results showing what circumstances should be taken into account when using these compounds in various areas (excited state deactivation in multiporphyrin complexes, photoinduced electron transfer, singlet oxygen generation). © ISUCT Publishing.
Mineeva I.V.,Belarusian National Technical University
Russian Journal of Organic Chemistry | Year: 2013
A simple and efficient asymmetrical synthesis was performed of a convenient bifunctional building block, methyl (R)-5,5-dimethoxy-3-methylpentanoate and its (S)-enantiomer. The possibility was shown of its application to the synthesis of insect pheromones. © 2013 Pleiades Publishing, Ltd.
Gaponenko M.,University of Neuchatel |
Kuleshov N.,Belarusian National Technical University |
Sudmeyer T.,University of Neuchatel
Optics Express | Year: 2014
We report on a diode-pumped Tm:KYW microchip laser generating 1 W continuous-wave output power. The laser operates at a wavelength of 1.94 μm in the fundamental TEM00 mode with 71% slope efficiency relative to the absorbed pump radiation and 59% slope efficiency relative to the incident pump radiation. The optical-to-optical laser efficiency is 43%. © 2014 Optical Society of America.
Pustovalov V.K.,Belarusian National Technical University |
Fritzsche W.,Institute of Photonic Technology
Plasmonics | Year: 2013
Modeling of nonlinear optical properties of spherical core-shell gold-silver and silver-gold nanoparticles (NPs) placed in water was carried out on the base of extended Mie theory. Efficiency cross sections of absorption σabs, scattering σsca, and extinction σext of radiation with wavelengths λ = 400 and 532 nm for core-shell NPs with constant core radii r00 = 5, 10, 20, and 40 nm and in the range of relative radii r1/r00 = 1-8 were calculated (r1 is the radius of shell). Dependences of optical properties of gold-silver and silver-gold NPs on increasing of core radius r0 in the range 0 - r1 under condition r1 = const and increasing of r0 under r1 - r0 = const were investigated. Results show the nonlinear behavior of optical properties of core-shell gold-silver and silver-gold NPs on radiation wavelengths (optical indexes of metals), different core and shell radii, and their correlation, on relative NP radii r1/r00. An increase and decrease of absorption, scattering, and extinction efficiency cross sections of core-shell NPs with changing of wavelengths, core and shell radii, and relative NP radii r1/r00 are established. These dependences can be used for experimental investigation of the interesting first stages of shell formation on core and optical determination of core-shell NP parameters. © 2013 Springer Science+Business Media New York.