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81.
82.
Light curves of 78 Herbig Ae/Be stars were studied by digital analysis methods. Twenty-five thousand photoelectricUBVR observations of these stars were made by the authors in 1978–1990. A star was usually observed once a night. The stars were observed between 70 and 770 nights and on average each star was observed at more than 300 nights. The mean epoch for a star is 5 years. A morphologic classification of the light curves is suggested. The method of digital analysis are briefly described. To estimate the reliability of cyclic phenomena discovered in our study, a large number of them has been examined.  相似文献   
83.
Hardware and software are developed for the first base seismic station in the modernized seismic subsystem for tsunami warning on Kamchatka. The station is formed as a seismic array. The structure of the equipment and its communication systems are described. The station is introduced into experimental operation. The first results of recording of a local strong earthquake at points of the Petropavlovsk station are discussed.  相似文献   
84.
The tectonic structure of the junction of the eastern Central Asian Fold Belt and the Siberian Platform, along with the deep structure of the Earth's crust and lithosphere in this region, has been described on the basis of new geological and geophysical data (seismic, geoelectric, and space-structural studies as well as new-generation geological maps), combined with new interpretation techniques (processing of the previous data by special software). The data suggest the existence of oblique collision during the convergence of the tectonic plates and, correspondingly, tectonic units composing these plates, when the Mongol–Okhotsk paleobasin closed. Such a scenario within the Aldan–Stanovoi Shield is evidenced by areas of syn- and postcollisional magmatism, with their deep-level and geochemical characteristics, and by the presence of a Late Mesozoic fold–thrust zone. Deep “traces” of these tectonomagmatic events, detected in the course of geological and geophysical modeling, are manifested in inclined deep boundaries between the crustal and lithospheric blocks. On the Earth's surface, they correspond to large fault systems: the Dzheltulak, North and South Tukuringra, Gulyui, and Stanovoi. It has been found that the influence of collision decreases northward with distance from the junction of the eastern Central Asian Fold Belt and the Siberian Platform (Dzheltulak and North Tukuringra transcrustal faults).  相似文献   
85.
The purpose of this work is to study the variability of the isotope composition (δ18О, δD, d exc) of the snow cover on a long transect of Western Siberia from the southern taiga to the tundra. The study of the snow cover is of paleogeographic, paleogeocryological, and paleohydrological value. The snow cover of western Siberia was sampled on a broadly NS transzonal profile from the environs of Tomsk (southern taiga zone) to the eastern coast of the Gulf of Ob (tundra zone) from February 19 to March 4, 2014. Snow samples were collected at 31 sites. Most of the samples represented by fresh snow, i.e., snow that had fallen a day before the moment of sampling were collected in two areas. In the area of Yamburg, the snow specimens collected from the surface are most probably settled snow of different ages. The values of δ18О in the snow from Tomsk to Yamburg varied from–21.89 to–32.82‰, and the values of δD, from–163.3 to–261.2‰. The value of deuterium excess was in the range of 4.06–19.53‰.  相似文献   
86.
This paper presents the results from the detailed analysis of aerial photographs and space images for the Kizimen area, which characterize the geologic and geomorphologic effects of the ongoing eruption over the 2010–2011 period. It is shown that the total volume (>0.5 km3) and total mass (>109 t) of the discharged (resurgent plus juvenile) material makes this eruption the most productive in Kamchatka for the first 12 years of the 21st century. The dominant component (>90%) is juvenile material with andesitic composition. The pyroclastics (tephra, deposits of the juvenile pyroclastic avalanches and incandescent debris avalanches) comprise >0.3 km3and >0.45× 109 t, the lava (a very thick block lava flow 3.052 km long and 2.163 km2 in area) occupies about 0.195 km3 and 0.45 × 109 t. With the exception of the tephra, which fell over an area of about 100000 km2, the rest of the material was accumulated on the Kizimen cone and at its base. The mean discharge rate of juvenile ejecta was about 15 m3/s (29 t/s) for 13 months (November 11, 2010 to December 11, 2011). Appreciable changes also occurred at the near-summit part of the volcano’s cone.  相似文献   
87.
We describe the future SMART-1 European Space Mission whose objective is to study the lunar surface from a polar lunar orbit. In particular, it is anticipated that selected regions of the Moon will be photographed using the AMIE camera with a mean spatial resolution of about 100 m in three spectral channels (0.75, 0.92, and 0.96 m) over a wide range of phase angles. Since these spectral channels and the AMIE resolution are close to those of the UVVIS camera onboard the Clementine spacecraft, the simultaneous processing of SMART-1 and Clementine data can be planned, for example, to obtain phase-ratio images. These images carry information on the structural features of the lunar surface. In particular, UVVIS/Clementine data revealed a photometric anomaly at the Apollo-15 landing site associated with the blowing of the lunar regolith by the lander engine. Anomalies were found in the ejection zones of several fresh craters.  相似文献   
88.
Doklady Earth Sciences - Based on long-term studies of a small sea in the Arctic Ocean, new regularities in the sedimentary process under the conditions of Arctic sedimentogenesis were established....  相似文献   
89.
The vertical fluxes of phytoplankton (VFPhyto) and particulate organic carbon (VFPOC) in the White Sea were determined using seven long-term (292 to 296 days) sediment traps moored at five stations at 67–255 m depths. The annual VFPhyto and VFPOC ranged from 0.55 to 24.64 g C/m2 and from 3.7 to 93.9 g C/m2, respectively. The highest VFPhyto was observed in the Basin region located close to the Gorlo along the Tersk coast. The algal biomass accounted for 15–43% of the VFPOC. Diatoms comprised the most important group, accounting for 83–100% in the sedimented biomass. Thalassiosira nordenskioeldii dominated in the VFPhyto at all the stations except for the station in the basin close to Onega Bay, where Ditylum brightwellii was the most abundant.  相似文献   
90.
Summary The radiation power a VLF loop antenna with an arbitrary orientation of the loop's plane relative to the direction of the external magnetic field is calculated and its portion, transferred to the electromagnetic part of the excited spectrum, is determined.
am umaa m uu am c nu umau nmu uma n m¶rt; a¶rt;um¶rt; n u n¶rt;a ma am mu uu, u¶rt;a ma¶rt;um am am cnma ¶rt;a au.
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