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Bishkek, Kyrgyzstan

Avtaeva S.V.,Kyrgyz Russian Slavic University | Sosnin E.A.,Institute of High Current Electronics | Saghi B.,University of Science and Technology of Oran | Panarin V.A.,Institute of High Current Electronics | Rahmani B.,University of Science and Technology of Oran
Plasma Physics Reports | Year: 2013

The influence of the chlorine concentration on the radiation efficiency of coaxial exciplex lamps (excilamps) excited by a dielectric barrier discharge (DBD) in binary Xe-Cl2 mixtures at pressures of 240-250 Torr is investigated experimentally and theoretically. The experiments were carried out at Cl2 concentrations in the range of 0.01-1%. The DBD characteristics were calculated in the framework of a one-dimensional hydrodynamic model at Cl2 concentrations in the range of 0.1-5%. It is found that the radiation intensities of the emission bands of Xe*2(172 nm) and XeCl* (308 nm) are comparable when the chlorine concentration in the mixture is in the range of 0.01-0.1%. In this case, in the mixture, the radiation intensity of the Xe*2 molecule rapidly decreases with increasing Cl2 concentration and, at a chlorine concentration of ≥0.2%, the radiation of the B → X band of XeCl* molecules with a peak at 308 nm dominates in the discharge radiation. The radiation efficiency of this band reaches its maximum value at chlorine concentrations in the range of 0.4-0.5%. The calculated efficiencies of DBD radiation exceed those obtained experimentally. This is due to limitations of the one-dimensional model, which assumes the discharge to be uniform in the transverse direction, whereas the actual excilamp discharge is highly inhomogeneous. The influence of the chlorine concentration on the properties of the DBD plasma in binary Xe-Cl2 mixtures is studied numerically. It is shown that an increase in the Cl2 concentration in the mixture leads to the attachment of electrons to chlorine atoms and a decrease in the electron density and discharge conductivity. As a result, the electric field and the voltage drop across the discharge gap increase, which, in turn, leads to an increase in the average electron energy and the probability of dissociation of Cl2 molecules and ionization of Xe atoms and Cl2 molecules. The total energy deposited in the discharge rises with increasing chlorine concentration due to an increase in the power spent on the heating of positive and negative ions. The power dissipated by electrons decreases with increasing chlorine concentration in the working mixture. Recommendations on the choice of the chlorine content in the mixture for reducing the intensity of VUV radiation of the second continuum of the Xe*2 excimer without a substantial decrease in the excilamp efficiency are formulated. © 2013 Pleiades Publishing, Ltd. Source

Dzhunushaliev V.,Kyrgyz Russian Slavic University | Dzhunushaliev V.,National Academy of Science Kyrgyz Republic
Annalen der Physik (Leipzig) | Year: 2010

It is shown that the Hamilton equations in supersymmetric quantum mechanics can be presented in nonassociative form, where the Hamiltonian is decomposed into two nonassociative factors. © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Avtaeva S.,Kyrgyz Russian Slavic University
European Physical Journal D | Year: 2014

Time-dependent characteristics of the dielectric barrier discharge in Xe-Cl2 mixture at chlorine concentration of 0.5% and kinetic processes governing the generation of XeCl∗ molecules are studied using the 1D fluid model. It is shown that at low voltage amplitude (5 kV) a one-peak mode of the discharge is observed and at high voltage amplitude (7 kV) a two-peak mode of the discharge appears. The radiation power of the XeCl∗ band increases with amplitude of the supply voltage. It is demonstrated that the harpoon reaction Xe∗ + Cl2 → XeCl∗ + Cl provides the greatest contribution into generation of XeCl∗ exciplex molecules during short current pulses and the ion-ion recombination Xe+ 2 + Cl- → XeCl∗ + Xe provides the greatest contribution during afterglow. Quenching of XeCl∗ molecules is a result of the radiative decay XeCl∗ → Xe + Cl + hv (308 nm). During current spike the great contribution into quenching of XeCl∗ provides also the dissociative ionization e + XeCl∗ → Xe+ + Cl + 2e. © 2014 EDP Sciences, SIF, Springer-Verlag Berlin Heidelberg. Source

Deev E.V.,Russian Academy of Sciences | Korzhenkov A.M.,Kyrgyz Russian Slavic University
Russian Geology and Geophysics | Year: 2016

The area of the Chon-Aksu and Kichi-Aksu grabens abounds in seismic deformation produced by historic and prehistoric events, among which the great Kemin (Kebin) earthquake of 1911, with a magnitude of Ms - 8 and a shaking intensity of I0 = 10-11, generated by the Aksu fault. Trenching across a fault scarp of the 1911 event has revealed signatures of reverse slip resulted from another earthquake that occurred about 3000 years ago. Traces of a large event at ~12,700 yr BP appear in sediments of a tectonically dammed lake. The trenching results, along with radiocarbon dating and published evidence, show the Late Pleistocene-Holocene history of the Aksu fault to comprise prolonged quiescence periods separated by large earthquakes or earthquake clusters at 19,500-20,000, 12,700, 4000-3000, and <850 yr BP (including the 1911 Kemin shock). © 2015. Source

Karaseva M.O.,Kyrgyz Russian Slavic University | Prakash S.,Atmospheric and Oceanic science Group | Gairola R.M.,Atmospheric and Oceanic science Group
Theoretical and Applied Climatology | Year: 2012

This paper presents the validation of monthly precipitation using Tropical Rainfall Measuring Mission Multisatellite Precipitation Analysis (TMPA)-3B43 product with conventional rain gauge observations for the period 1998-2007 over Kyrgyzstan. This study is carried out to quantify the accuracy of TMPA-3B43 product over the high latitude and complex orographic region. The present work is quite important because it is highly desirable to compare the TMPA precipitation product with the ground truth data at a regional scale, so that the satellite product can be fine-tuned at that scale. For the validation, four different types of spatial collocation have been used: station wise, climatic zone wise, topographically and seasonal. The analysis has been done at the same spatial and temporal scales in order to eliminate the sampling biases in the comparisons. The results show that TMPA-3B43 product has statistically significant correlation (r = 0.36-0.88) with rain gauge data over the most parts of the country. The minimum linear correlation is observed around the large continental water bodies (e. g., Issyk-Kul lake; r = 0.17-0.19). The overall result suggests that the precipitation estimated using TMPA-3B43 product performs reasonably well over the plain regions and even over the orographic regions except near the big lake regions. Also, the negative bias suggests the systematic underestimation of high precipitation by TMPA-3B43 product. The analyses suggest the need of a better algorithm for precipitation estimation over this region separately to capture the different types of rain events more reliably. © 2011 Springer-Verlag. Source

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