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A gamma ray spectrometer recording on the surface of Venus from Venera 8 reveals a content of radioactive potassium, uranium, and thorium very similar to acid magmatic rocks on the Earth. Venus is evidently a differentiated planet. 相似文献
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We analyze photometric and spectroscopic observations of the close binary system V664 Cas. All the characteristics of its radiation are consistent with the star being a cataclysmic variable with powerful reflection effects. The orbital period is refined (P=0.5816475 d) and the ephemerides of the system determined. The U, B, V, R light curves of V664 Cas display sinusoidal variations with similar amplitudes near Δm=1.1m. This suggests that a hot spot on the surface of the secondary always dominates the optical radiation of the system. The spectra contain emission lines, two-peaked hydrogen lines, and narrow lines of helium and heavy elements in high ionization states, whose intensities vary synchronously with the brightness. The HeII λ4686 Å line has broad absorption wings that form in the atmosphere of the O subdwarf. The mass function, f(m)=0.007M⊙, is the lowest among all precataclysmic variables: the mass of the secondary exceeds the mass of the primary by more than a factor of 1.6. A full set of fundamental parameters for V664 Cas is determined based on modeling of the spectra and light curves, taking into account reflection effects in the system. Most of the emission lines are formed under conditions of appreciable deviations from local thermodynamic equilibrium. The possibility of carrying out correct modeling of the Balmer-line profiles assuming the stellar radiation is absorbed in a planetary nebula is demonstrated. 相似文献
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The problem of comparison of the composition of crystalline rocks with the composition of the constituent minerals of these rocks is considered. It is proposed to present the composition of rocks and the compositions of the constituent minerals in the form of a triangle on the plane. The experience of presentation of compositions in phase diagrams was taken as a basis for the construction. Analysis of the crystallochemical characteristics of clinopyroxenes and garnets has shown that three parameters are enough for depicting the compositions of these and other minerals. For this purpose, similar composition components of rocks and their minerals are summarized in molecular proportions and are plotted on the triangle DO-1/2(R2O3)-XO2, where DO = (MgO + CaO + FeO + MnO + NiO + ...) + 1/4(Na2O + Al2O3) + 1/4(K2O + Al2O3), 1/2(R2O3) = 1/2(Al2O3 + Fe2O3 + Cr2O3 + ...) - (1/4(Na2O + Al2O3) + 1/4(K2O + Al2O3)), and XO2 = SiO2 + TiO2. The compositions of minerals are expressed as the sums of their components: Ol = Fo + Fa + Lar + Neph + ..., Px = Di + En + Wol + Ged + Gip + Jd + Eg + ..., Ga = Pyr + Gross + Alm + Spe + Ski + Knr + Mj + ..., etc. A step-by-step calculation algorithm is proposed, which permits evaluation of the contents of bi- and trivalent iron during probe microanalyses of garnets and pyroxenes. Comparison of the compositions of deep-seated rocks and their minerals shows their good consistency. The proposed schematic projection permits a visual comparison of the compositions of rocks with low contents of carbonates and water, from ultrabasic (e.g., dunites) to acid (e.g., granites) ones. 相似文献
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O.Molchanov E.Fedorov A.Schekotov E.Gordeev V.Chebrov V.Surkov A.Rozhnoi S.Andreevsky D.Iudin S.Yunga A.Lutikov M.Hayakawa P.F.Biagi 滕荣荣 《世界地震译丛》2009,(2):40-52
介绍了大气层和电离层震前现象机制的基本观念。简短回顾了观测结果后,我们得出结论：1．流体下层物质（气泡）向上迁移能导致近地表的热水／气体被逐出,并在强度弱化的地区引发地震;2．因此,气泡出现的时间和地点是随机的,但是地震、地球化学异常和前震（地震、SA和超低频电磁异常）是随机关联的;3．大气温度和密度扰动跟随着震前热水／气体释放,导致产生周期为6～60min的大气重力波（AGW）;4．地震引发的大气重力波能导致电离层扰动变化并导致大气层中地平线上无线电波传播、下部电离层低频波扰动和地面超低频辐射衰减的变化。 相似文献
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O. A. Pokhotelov M. Parrot E. N. Fedorov V. A. Pilipenko V. V. Surkov V. A. Gladychev 《Annales Geophysicae》1995,13(11):1197-1210
A review is presented of the effects influencing the ionosphere which are caused by acoustic emission from different sources (chemical and nuclear explosions, bolides, meteorites, earthquakes, volcanic eruptions, hurricanes, launches of spacecrafts and flights of supersonic jets). A terse statement is given of the basic theoretical principles and simplified theoretical models underlying the physics of propagation of infrasonic pulses and gravity waves in the upper atmosphere. The observations of “quick” response by the ionosphere are pointed out. The problem of magnetic disturbances and magnetohydrodynamic (MHD) wave generation in the ionosphere is investigated. In particular, the supersonic propagation of ionospheric disturbances, and the conversion of the acoustic energy into the so-called gyrotropic waves in the ionospheric E-layer are considered. 相似文献
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Izvestiya, Physics of the Solid Earth - Abstract—Anomalous variations in radon emissions from the soil are sometimes observed before and after strong earthquakes. In this paper, we... 相似文献
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A program of the search for and analysis of profile variability in the spectra of bright O supergiants with a time resolution of 5–30 min is described. Preliminary results of the spectroscopic observations of the stars λ Ori, α Cam, and 19 Cep with the 1-m Special Astrophysical Observatory telescope in 2001 are presented. Line-profile variability was detected in the spectra of all the stars studied; variability in the Hα and C III λ5696 Å lines in the spectrum of λ Ori has been found for the first time. The variability amplitude is 4–5% for 19 Cep and 1–2% for α Cam and λ Ori on time scales from several hours to 3 or 4 days, and the width of the variable features reaches 2 Å (100 km s?1). We detected cyclical variations in the He II λ4686 and C III λ5696 line profiles in the spectrum of λ Ori on time scales of 1.3–1.6 days. Rapid profile variations on time scales of 3.5–7 h were found in the violet parts of the Hα and He I λ4715 line profiles in the spectrum of λ Ori A. 相似文献
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We examine the factors that are responsible for the formation of the beaded structure of channels in the permafrost zone. It is found that formation of beaded channels in the permafrost zone is possible only in the case of small gradients and water flow rates. The existence of such channels in the permafrost zone is unstable; hence, there is little likelihood that they have persisted in a relict form to date 相似文献