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901.
Shock metamorphism of the lunar samples is discussed. All types of lunar glasses formed by various-size collision-type impact are found as impact glass, ropy glass and agglutinates. The agglutinates bonded by crystal and glassy materials contain hydrogen and helium from the solar wind components. Lunar shocked minerals of plagioclase and silica show anomalous compositions and densities. There are typical two formation processes on planetary materials formed by shock events; that is (1) shocked quartz formed by silica-rich target rocks (esp. on evolved planets of the Earth and Mars), and (2) shocked silica with minor Al contents formed from plagioclase-rich primordial crusts of the Moon. The both shocked silica grows to coarse-grain normal crystals after high-temperature metamorphism which cannot distinguish the original main formation event of impact process. 相似文献
902.
周训 《地球科学与环境学报》1992,(3)
本文以四川盆地中部的L_1井为例,讨论深层卤水自喷钻井卤水产出特征、水文地球化学特征和开采动态特征,并对钻井的测试资料进行分析,预测该钻井的卤水可采资源量。 相似文献
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908.
Stephen Serjeant Duncan Farrah James Geach Toshinobu Takagi Aprajita Verma Ali Kaviani Matt Fox 《Monthly notices of the Royal Astronomical Society》2003,346(4):L51-L56
We present the K -band Hubble diagrams ( K – z relations) of submillimetre-selected galaxies and hyperluminous galaxies (HLIRGs). We report the discovery of a remarkably tight K – z relation of HLIRGs, indistinguishable from that of the most luminous radio galaxies. Like radio galaxies, the HLIRG K – z relation at z ≲ 3 is consistent with a passively evolving ∼3 L * instantaneous starburst starting from a redshift of z ∼ 10 . In contrast, many submillimetre-selected galaxies are ≳2 mag fainter, and the population has a much larger dispersion. We argue that dust obscuration and/or a larger mass range may be responsible for this scatter. The galaxies so far proved to be hyperluminous may have been biased towards higher AGN bolometric contributions than submillimetre-selected galaxies due to the 60-μm selection of some, so the location on the K – z relation may be related to the presence of the most massive active galactic nucleus. Alternatively, a particular host galaxy mass range may be responsible for both extreme star formation and the most massive active nuclei. 相似文献
909.
As in the first part of the present study (Sapar et al., 2002) we use the β-law for velocity of stellar wind and the Sobolev
approximation for radiative transfer. Here we have succeeded to derive general and relatively simple analytical formulae in
elementary functions for saturated P Cygni type line profiles if parameter 2β is arbitrary positive integer (in the first
part we studied the cases 2β ≤ 4). The four terms obtained describe contributions to the line profile due to isotropic and
anisotropic parts of optical thickness in the source function of the light-scattering layer followed by isotropic and anisotropic
parts of multiple scattering. The limits of acceptability of the Sobolev approximation for β-law have been discussed and specified.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
910.
Summary The unprecedented quality of the IRAS data prompted a series of papers reinvestigating the origin of the galactic infrared/submillimeter radiation and the nature of the heating sources of the interstellar dust. The scope of this paper is to review the main results of these new studies. Sect. 1 contains a general introduction to the subject and an overview of the earlier work. In Sect. 2 and 3, we summarize our current knowledge on dust properties and on the interstellar radiation field. Then, we present the recent interpretations of the infrared emission of our Galaxy, which are based on the IRAS data: in Sect. 4 we present the results from the galactic disk; Sect. 5 covers the question of the contribution from small dust particles, and in Sect. 6 we describe the infrared radiation from the galactic center. The nature of the heating sources and the origin of the galactic infrared radiation is then discussed in Sect. 7. Finally, Sect. 8 presents a comparison of our Galaxy with external galaxies 相似文献