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1.
T. Sergienko I. Kornilov E. Belova T. Turunen J. Manninen 《Journal of Atmospheric and Solar》1997,59(18):2401-2407
Ionospheric heating experiments were done by the EISCAT Heater in Tromsø on 15–19 November, 1993. A low-light TV camera was installed at the VLF receiving station at Porojärvi about 100 km to the south-east of Tromsø. The spectral analysis of the auroral luminosity variations showed that the brightness of the aurora varied at the modulation frequency of the heating wave. The results of this analysis and the numerical simulations of the auroral luminosity variations caused by the HF heating are shown. The variations of the optical emission intensity at the heating frequency occur during the auroral ionosphere modification. The observed intensity variation of the auroral green line during the interval of enhanced electron temperature is explained by a decreasing rate of the O2+ ion dissociative recombination when the electron temperature increases. The brightness variation depends on the characteristic energy and the intensity of the auroral electron flux and the heating wave parameters. The artificial luminosity pulsations caused by HF heating are estimated. 相似文献
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Ionosphere-magnetosphere disturbances at high latitudes, e.g. magnetic substorms, are accompanied by energetic particle precipitation and strong variations of the ionospheric electric fields and currents. These might reasonably be expected to modify the local atmospheric electric circuit. We have analysed air-earth vertical currents (AECs) measured by a long wire antenna at Esrange, northern Sweden during 35 geomagnetic substorms. Using superposed epoch analysis we compare the air-earth current variations during the 3 h before and after the time of the magnetic X-component minimum with those for corresponding local times on 35 days without substorms. After elimination of the average daily variation we can conclude that the effect of substorms on AEC is small but distinguishable. It is speculated that the AEC increases observed during about 2 h prior to the geomagnetic X-component minimum, are due to enhancement of the ionospheric electric field. During the subsequent 2 h of the substorm recovery phase, the difference between substorm and quiet atmospheric currents decreases. The amplitude of this substorm variation of AEC is estimated to be less than 50% of the amplitude of the diurnal variation in AEC during the same time interval. The statistical significance of this result was confirmed using the Van der Waerden X-test. This method was further used to show that the average air-earth current and its fluctuations increase during late expansion and early recovery phases of substorms. 相似文献
3.
T. P. Belova 《Journal of Volcanology and Seismology》2017,11(2):136-142
We studied the extraction of boron and lithium from prepared and industrial solutions using industrial ionites ATsD-4-1p, AV-16 GS, AN-3, and AV-17-8 and by modified zeolites from the Yagodnoe field, Kamchatka. The modification was performed using aluminum hydroxide, hydrochloric hydroxylamine, or urotropin. We found that when modified with Al(OH)3, zeolite shows selectivity with regard to lithium ions. When modified with hydrochloric hydroxylamine or with urotropin zeolites can be used for sorption of boric acid from naturally occurring and industrial solutions. The sorptive capacity of the modified zeolites is 30% higher on average compared with that of industrial ionites. 相似文献
4.
Water–rock–gas system is simulated using a technique based on the fundamental principles of modern hydrogeochemistry regarding the formation parameters of natural-water chemistry to show that groundwater pollution hazard at a gold-bearing placer is acute for any site of water exchange changing from passive to active. Under passive water exchange, the products of sulfide oxidation are accumulated; whereas under active water exchange, the oxidation products are leached out to form acid drainage flows. The treatment of acid drainage water and the neutralization of acid solutions are more effective under reduction or weakly alkaline conditions. 相似文献
5.
The results of many-year studies of production destruction processes in the Mozhaisk Reservoir are used to examine their specific features in extremely dry years. It is shown that the processes of organic matter formation and destruction in the reservoir are more active when water level is low. Variations in the intensity of production-destruction processes in all phases of synoptic cycle are analyzed (during cooling, cold, heating, and warm). Changes in weather conditions are shown to be accompanied by phytocenosis restructuring. Fine-cell phytoplankton forms are shown to dominate in phytocenosis composition when water level in the reservoir is extremely low. 相似文献
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Data of observations made in 1967–1996 on the Mozhaisk Reservoir were used to examine the dynamics of primary production and destruction and their proportion. The species and size structure of the phytoplankton community was found to have changed significantly and the community biomass, to have increased in the course of long-term succession. 相似文献
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The influence of various chemical elements on radiative cooling of the gas flowing from a viscous jump is investigated in a model with a stationary shock in the atmosphere of a cool star. A closed system of equations is written for the thermal energy per heavy particle, the electron temperature, and the relative concentrations of elements in all ionization states. In addition to hydrogen and helium, atomic, singly ionized, and doubly ionized carbon, nitrogen, oxygen, sodium, magnesium, aluminum, silicon, sulfur, potassium, calcium, and iron are included, assuming they have their normal cosmic abundances. The high optical depth in Lyman-series lines leads to a return of the thermal energy to electrons via secondary collisions. As a result, the contribution of hydrogen to the cooling rate falls to the level of the contribution of metals, mainly carbon, magnesium, and iron. Thus, such shock models are able to explain the presence of bright metal lines in the spectra of cool and solar-type stars. 相似文献
8.
N. P. Akmet’eva S. E. Belova R. G. Dzhamalov I. S. Kulichevskaya E. E. Lapina A. V. Mikhailova 《Water Resources》2014,41(4):353-363
The dynamics of natural recovery of bog massifs in Tver oblast, which suffered from fire in 2010, is discussed. The presented conclusions are based on three-year field observations at check sites of Galitskii mokh bog along with monitored variations of the physicochemical properties of peat ash and pyrolyzed peat, bog water chemistry, the development of microbial communities, and vegetation recovery. Moreover, some features of bog massif flooding are discussed. 相似文献
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Ordovician complexes of the convergent margins of lithospheric plates are established in the Paleozoides of the southern Urals. Several types of Ordovician sections that make up allochthons and characterize different geodynamic settings are thoroughly studied and dated on the basis of conodont biostratigraphy. The geochemistry and petrology of volcanic rocks bear information on the evolution of the Paleoural ocean and the convergent relationships of plates from the end of the Llanvirnian. The suprasubduction volcanic activity in the Late Ordovician gave way to within-plate volcanism of extension zones, the development of which continued into the Early Silurian. 相似文献