2011, Vol. 08 No. 1(15)

  1. V.I. Oleshko, S.S. Vil’chinskaya, S.G. Gorina. Time-resolved luminescent spectrometry of zink selenide crystals..
    [article]
    Summary

    The spectral and kinetic characteristics of pulse cathodoluminescence of undoped ZnSe single-crystals grown by sublimation from the vapor phase (Davydov-Markov method) and by flux growth (Bridgman method) have been measured. Three groups of bands were found in the spectra of radiative recombination of zinc selenide: exciton, edge emission and bands due to the recombination of carriers in deep centers. The spectral-kinetic characteristics of the edge emission in ZnSe crystals with different previous history have been studied. It was found that the number of edge emission series, the ratio of their intensities and spectral position are to be determined by the previous history of crystals. It is shown that the total intensity of the edge emission reduces more than tenfold with the temperature increase in the range of 15 – 80 K. The results obtained show that the properties of the edge emission can be well described by the model of donor-acceptor pairs..

  2. V.M. Jurov Superficial tension of pure metals
    [article]
    Summary

    In work questions of experimental definition of a superficial tension of massive samples and nanoparticles pure metals are considered. The model allowing with good accuracy to define size of a superficial tension, its dependence on temperature and on the size of particles is offered. Results of calculations are compared to known models and a method of “zero creep».Work is executed within the limits of the Program of basic researches of Ministry of Education and Science of the Republic of Kazakhstan. The grant 1034 FI. .

  3. K. S. Baktybekov, M.K. Myrzakhmet, M. Nikl, V. Jerry, K. Bekmyrza.About luminescent properties of monocrystals of the difficult sulfates activated by thallium.
    [article]
    Summary

    Luminescence centres in the ammonium sulphate crystals with an impurity of thallium and in the mixed crystals are explored. It is shown, that these centres are the one-charging thallium ion. Two various positions of replacement feeblly affect scintillation performances of these crystals.

  4. I.V. Poyarkov Gravitational convection in gas system Ar – N2.
    [article]
    Summary

    A study has been made of the “diffusion – gravitational convection” transition boundary in an argon-nitrogen binary system at different pressures and a constant temperature gradient. Research relative influence two gradients (concentration and temperature) to the density gradient. In a binary system with an unstable stratification of the density observe two mixing regimes – diffusion and convective mass transfer. It has been shown that in the case of isothermal and non-isothermal mixing, the diffusion process is stalled at one and the same pressure. The convective mass transfer becomes less intensive in the presence of a temperature gradient.

  5. Z.Zh. Zhanabayev, T.Yu. Grevtseva. Nonlinear fractals and exciton formations in nanostructured semiconductors
    [article]
    Summary

    We suggest the fractal model for the description of exciton spectra in amorphous and porous semiconductors. Because of theirs chaotic structure the well-known analogy of exciton with hydrogen-like atom is insufficient.We obtain equations for energy of exciton, biexciton and trion depending on photon energy. Comparison of results of our theory to the recent experimental data is given in the paper. Theory shows the existence of most universal regularities of dynamical systems.

  6. L. Minkov, M. Farghaly, J. Dueck. Hydrodynamics of hydrocyclone with built-in water injector
    [article]
    Summary

    The paper considers the numerical simulation of 3D fluid dynamics based on the k-eps RNG model of turbulence in the hydrocyclone with the injector, containing 5 tangentially directed nozzles. The simulation results are supported by experimental research. It is shown that the direction of movement of injected fluid in the hydrocyclone depends on the water flow rate through the injector. Experiments and calculations show that the dependence of the Split-parameter on the injected water flow rate has a non-monotone character associated with the ratio of power of the main flow and the injected fluid..

  7. Y. M. Smirnov, B.M. Kenzhin, M.A. ZhurunovaThe results of “Vibration-seismic-module-solid massif-disturbance” system simulation modeling.
    [article]
    Summary

    Paper is devoted to study of interaction of a mechanic harmonic generator – the vibration-seismic module – and a coalbed. As a result there are qualitative and quantitative dependences of distribution of elastic seismic ostillations in a coalbed..

  8. D.M. Zakiev, G.P.Amochaeva, R.A. Mursalin. .Analysis of the procedure lcas in transport networks NGSDH.
    [article]
    Summary

    The paper presents a procedure LCAS (Link Capacity Adjustment Scheme) – scheme of regulation of channel capacity, is built on virtual concatenation mechanism. LCAS protocol allows you to dynamically change the capacity of the channel without interference from staff. In particular, it is interesting to create a model protocol on one of the most common programming languages, since the simulation to evaluate the effectiveness of almost any technology to run it in operation..

  9. Zh.K. Ishchnova, G.P. Amochaeva, A.K. Tussupbekova. Research of Influence of speech codecs on transmission quality of the digital signal
    [article]
    Summary

    The Kazakhstan telephone system of the general using contains both analog and digital segments. For a long time analog segments served for an information exchange between subscribers, however introduction of digital segments has led qualitative information transfer for long distances because digital technologies possess a number of advantages.