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Radiophysics and Quantum Electronics - We present the results of comparing the total electron content measurements based on GLONASS satellite signals and the EISCAT UHF incoherent scatter radar...  相似文献   
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An investigation was made into the nature of paramagnetic centers in a Tc/Al2O3 system under varying conditions as to heat treatment and technetium content, and in O2 and CO adsorption environments. It was found that in the case of reduction at 573 K Tc2+ ions and, conceivably, other ionic forms developed and stabilized on the carrier surface. After reduction at 973 K two types of electron center appeared, whose concentration increased as reduction was prolonged. Signals were observed in the low fields (3–20 mT) of the ESR spectra having g1 13.5 and g2>30, which could be assigned to free charge carriers in a cluster of metal atoms or ions. Adsorption of O2 at 300 K caused O 2 ion radicals to form on the surface of the reduced Tc/Al2O3 samples, both electron centers and technetium ions constituting the electron donors. In the case of CO adsorption paramagnetic (CO) 2 particles appeared on the Tc/Al2O3 samples after prolonged exposure. On reaction with O2 two types of O 2 ion-radical with differing thermal stability were formed.Institute of Physical Chemistry, Russian Academy of Sciences, Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 9, pp. 1972–1978, September, 1992.  相似文献   
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1.  The authors have studied the formation of electron and hole paramagnetic centers in gamma-irradiated magnesium hydroxide and oxide with various degrees of dehydration.
2.  Rise in the temperature of preliminary heat treatment of the magnesium oxide causes an increase in the radiation-chemical yield of FS + centers and a decrease in that of V su centers.
3.  The thermal stability of paramagnetic centers in magnesium oxide increases as the hydroxyl group content decreases.
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We present the first results of observations of the stimulated electromagnetic emission (SEE) in the ionosphere modified by the Space Plasma Exploration by Active Radar (SPEAR) heating facility. Observation of the SEE is the key method of ground-based diagnostics of the ionospheric plasma disturbances due to high-power HF radiation. The presented results were obtained during the heating campaign performed at the SPEAR facility in February–March 2007. Prominent SEE special features were observed in periods in which the critical frequency of the F 2 layer was higher than the pump-wave frequency (4.45 MHz). As an example, such special features as the downshifted maximum and the broad continuum in the region of negative detunings from the pump-wave frequency are presented. Observations clearly demonstrate that the ionosphere was efficiently excited by the SPEAR heating facility despite the comparatively low pump-wave power. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 951–955, November 2008.  相似文献   
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We obtain a complete classification of I-maximal subalgebras of rank n of the conformal algebra AC(1, n). Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 4, pp. 459–470, April, 1998.  相似文献   
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We present the results of first studies of the modification of the ionosphere by high-power HF radiation, which were obtained using signals of high-orbit GPS/GLONASS navigation satellites. Enhancement of the ionospheric modification in the magnetic-field direction was observed for the first time. This leads to a total decrease in electron number density and the formation of electron density irregularities near the magnetic-zenith direction. The efficiency of using GSP/GLONASS satellite signals for the studies of the ionosphere modified by HF radiation is demonstrated. Prospects for further studies in this field are discussed. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 11, pp. 934–938, November 2008.  相似文献   
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The paper examines the effectiveness of using explosive energy to compact the soil in water-filled channels in order to reduce seepage losses. The study was conducted using simulation and approximate analytical methods.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 58, pp. 56–61, 1986.  相似文献   
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