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A. I. Sukhorukov 《Annales Geophysicae》1996,14(1):33-41
Tweek atmospherics generated by lightning discharges and propagated in the night-time Earth-ionosphere waveguide, have often very pronounced dispersive features near the first few waveguide cut-off frequencies (fcm\simm\dot{s}fc1, fc1\sim1.6-1.9 kHz, m=1, 2, ...,), being very extended in time, and have rather large amplitudes of oscillations with periods corresponding to the narrow vicinity of the cut-off frequencies. In this paper an analytical approach is developed to describe the waveform of distant tweeks. It is based on the solving of the Maxwell equations in two qualitatively different regions, whose changes are related in the first instance to the changes in the relative magnitudes of the displacement current and components of the conduction currents, and the following asymptotic matching of the solutions in the transitional region. The analytical night-time waveguide model accounts for both anisotropy and vertical inhomogeneity of the low ionosphere. The model is valid for upper ELF - lower VLF range and is well suitable for the analysis of the QTEm modes in the cut-off frequency regions, which determine the most important part of the tweek spectra and tweek amplitudes. The influence of the different ionospheric heights on the tweek characteristics is determined. The efficiency of the tweek generation by cloud-to-cloud discharge is also evaluated. 相似文献
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N. V. Dmitriev S. M. Likhachev V. F. Raputa V. A. Sukhorukov 《Physical Oceanography》1992,3(2):123-129
The sensitivity of upper mixed layer models developed at the Computer Centre of the Siberian Department, USSR Academy of Science, using oceanographic observations conducted at station C, to seasonal variability of the Prandtl number and short-wave radiance absorption coefficient is studied. A quantitative criterion for estimating the validity of the upper ocean model is suggested.Translated by V. Puchkin. 相似文献
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A. V. Chuguevskii F. V. Sukhorukov M. S. Mel’gunov I. V. Makarova A. T. Titov 《Doklady Earth Sciences》2010,430(1):51-53
The radioisotope compositions, structure, and behavior of “hot” particles under the natural conditions of the Yenisei River
in the nearby influence zone of Krasnoyarsk mining and chemical combine were examined in this study. By the composition of
gamma-radiating isotopes, all particles are divided into three groups: mono-isotopic, bi-isotopic and poly-isotopic. Mono-isotopic
“hot” particles, containing only 60Co were discovered for the first time. Transuranium elements (241Am and 243Cm) were revealed in poly-isotopic particles. Investigation of poly-isotopic particles by means of a scan electron microscope
showed that the presence of UO2 together with the lack of activation of 152Eu testifies to the reactor origin of this particle. Experiments showed that in natural conditions “hot” particles under the
influence of filtrating water and moisture of pore solutions are gradually dissolved and radionuclides are repeatedly drawn
into migration. 相似文献
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Chronicle
70th Anniversary of Anatolii Maksimovich Nikanorov 相似文献6.
A.I. Sukhorukov 《Planetary and Space Science》1991,39(12):1673-1676
A conductive ionosphere and a totally non-conductive layer of the atmosphere close to the surface of the planet form a quasispherical concentric resonator. This provides in principle for the possibility of the existence of global resonances of an electromagnetic field generated by thunderstorm activity or by hydromagnetic waves excited in an upper ionosphere and transformed into ordinary electromagnetic waves while penetrating the resonator. We have obtained an estimate of resonance frequencies of a Martian resonator: ƒ1 13–14 Hz,ƒ2 24–26 Hz, ƒ3 35–38 Hz, etc. for two essentially different models of electron density distribution in the low ionosphere of Mars. The corresponding estimated quality values are low: Qn 2–4. A relatively wide range of the quality variation depending on a model of averaged altitudinal electron density distribution in the low ionosphere of Mars yields the criterion for an adequate model. 相似文献
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This work reports the first discovery of sapphirine-bearing mineral parageneses in granulites of the Angara–Kan block, information on the mineral assemblage of rocks, and the mineral composition. Based on mineral geothermometers utilizing alumina content in orthopyroxene, reconstruction of the composition of ternary feldspar, and the titanium content in zircon, it was revealed that the peak temperatures of metamorphism reached 1100°C, after which the rocks underwent cooling under sub-isobaric conditions. It is assumed that the pulse of ultra-high-temperature metamorphism correlates with processes of extension and intraplate magmatism during the age interval of 1.78–1.75 Ga. 相似文献
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F. I. Zhimulev Yu. A. Kalinin V. P. Sukhorukov E. De Pelsmaeker M. Poujol K. R. Kovalev S. Glorie E. A. Naumov R. Seltmann J. De Grave 《Doklady Earth Sciences》2018,481(2):1033-1036
Accessory zircon from the polyphase Raygorodok stock (Northern Kazakhstan) has been dated by local U–Pb analysis (SIMS and LA-ICP-MS). This Au-bearing intrusion has been dated to 442–447 Ma, suggesting its emplacement at the very end of the Ordovician and Early Silurian, allowing the stock’s correlation with the Stepnyak Complex of small intrusions. Thus, control of small intrusions of the Stepnyak type over gold mineralization has been corroborated permitting their use as a regional prospecting characteristic. 相似文献
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A. A. Spivak S. A. Kozhukhov M. V. Sukhorukov V. A. Kharlamov 《Izvestiya Physics of the Solid Earth》2009,45(2):118-133
The results of measurements of the volumetric activity of subsurface radon Rare given for several sections of the Earth’s crust located within the central part of the East European Platform. The influence of tectonic structures on the spatial zonality of radon emanation and the intensity of its temporal variations is shown. The temporal variations in radon emanation are characterized by periodicity with periods of approximately a day, as well as of 4, 14, and 29 days, and, as correlation analysis shows, they are determined by the cyclic recurrence of tidal deformations and by cyclonic processes in the atmosphere. The high correlation of the mean values of the volumetric activity of subsurface radon with the value of atmospheric pressure is established. The dependence of the volumetric activity of subsurface radon and its temporal variations on the depth within the range of depths 0.8–11.5 m is determined. As a result of laboratory experiments, the nonlinear nature of the dependence of radon emanation on the frequency of vibration action is established. For granites, the intensity of radon emanation is maximal at frequencies of 16 and 32 Hz. The results of complex measurements of the microseismic background and the volumetric activity of subsurface radon carried out in the region of the Nelidovo-Ryazan tectonic structure demonstrate the high correlation between the volumetric activity of subsurface radon and the relative amplitude of the quasi-monochromatic component of the microseismic background with a peak frequency of 16.5 Hz. 相似文献