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991.
戴剑平 《广东海洋大学学报》2006,26(2):128-131
影视艺术欣赏是人类在精神上对美的需求且与其对应的、按美的法则建造的“第二自然”,具有审美属性;是一种审美创造与审美关系。从悲剧、悲剧感,喜剧和喜剧感及其审美价值等方面均可印证这一说法。 相似文献
992.
Multi-object spectroscopy of the field surrounding PKS 2126−158: discovery of a z= 0.66 galaxy group
Matthew T. Whiting Rachel L. Webster Paul J. Francis 《Monthly notices of the Royal Astronomical Society》2006,368(1):341-350
The high-redshift radio-loud quasar PKS 2126−158 is found to have a large number of red galaxies in close apparent proximity. We use the Gemini Multi-Object Spectrograph (GMOS) on Gemini South to obtain optical spectra for a large fraction of these sources. We show that there is a group of galaxies at z ∼ 0.66 , coincident with a metal-line absorption system seen in the quasar's optical spectrum. The multiplexing capabilities of GMOS also allow us to measure redshifts of many foreground galaxies in the field surrounding the quasar.
The galaxy group has five confirmed members, and a further four fainter galaxies are possibly associated. All confirmed members exhibit early-type galaxy spectra, a rare situation for a Mg ii absorbing system. We discuss the relationship of this group to the absorbing gas, and the possibility of gravitational lensing of the quasar due to the intervening galaxies. 相似文献
The galaxy group has five confirmed members, and a further four fainter galaxies are possibly associated. All confirmed members exhibit early-type galaxy spectra, a rare situation for a Mg ii absorbing system. We discuss the relationship of this group to the absorbing gas, and the possibility of gravitational lensing of the quasar due to the intervening galaxies. 相似文献
993.
Cheng-Yue Su Yi-Ping Qin Jun-Hui Fan Zhang-Yu Han National Astronomical Observatories/Yunnan Observatory Chinese Academy of Sciences Kunming Graduate School of Chinese Academy of Sciences Beijing Department of Physics Guangdong University of Technology Guangzhou Center for Astrophysics Guangzhou University Guangzhou Department of Mechanics University of Science Technology of China Hefei 《中国天文和天体物理学报》2006,6(3):323-330
We investigate the forming of gamma-ray burst pulses with a simple one-dimensional relativistic shock model. The mechanism is that a "central engine" drives forward the nearby plasma inside the fireball to generate a series of pressure waves. We give a relativistic geometric recurrence formula that connects the time when the pressure waves are produced and the time when the corresponding shocks occurred. This relation enables us to relate the pulse magnitude with the observation time. Our analysis shows that the evolution of the pressure waves leads to a fast rise and an exponential decay pulses. In determining the width of the pulses, the acceleration time is more important than that of the deceleration. 相似文献
994.
995.
城市垃圾的生物处理技术 总被引:1,自引:0,他引:1
生物技术是实现城市垃圾无害化和资源化的一种有效手段。重点阐述了城市垃圾生物处趣的基本原理及3种主要的生物处理方法,简要介绍了城市垃圾生物处理方法中的一些新技术及发展趋势,为寻找适合我国国情的垃圾处理技术提供一些参考。 相似文献
996.
In this article we present different aspects of AGN studies demonstrating the importance of the UV spectral range. Most important diagnostic lines for studying the general physical conditions as well as the metalicities in the central broad line region in AGN are emitted in the UV. The UV/FUV continuum in AGN excites not only the emission lines in the immediate surrounding but it is responsible for the ionization of the intergalactic medium in the early stages of the universe. Variability studies of the emission line profiles of AGN in the UV give us information on the structure and kinematics of the immediate surrounding of the central supermassive black hole as well as on its mass itself. 相似文献
997.
R. F. González G. Montes J. Cantó L. Loinard 《Monthly notices of the Royal Astronomical Society》2006,373(1):391-396
In this paper, we compute theoretically the flux density and the spectral index of the free–free radiation at radio wavelengths produced by shocks in the inner bipolar emission nebula called the little Homunculus around the star η Carinae. The little Homunculus is believed to have formed as a result of the minor eruption suffered by the star in the 1890s. In our model, we consider a simplified interacting stellar wind scenario where the post-outburst η Carinae wind collides with the eruptive outflow (both assumed to be bipolar with conical symmetry). As a result of the interaction, shock-wave structures are formed and generate the development of two polar caps moving in opposite directions. After ∼100 yr (i.e. at present times), the polar caps are located ±2.3 arcsec on each side of the star, and remain embedded within the larger bipolar Homunculus that extends from −8 to +8 arcsec along its major axis. Using observational estimates of the characteristics of the eruptive event of the 1890s, and of the ambient wind powered by η Carinae in the decades after the eruption ended, we study the evolution of the polar caps formed as a result of a sudden increase in the wind velocity and an instantaneous drop in the mass-loss rate (just after the eruption) at the injection radius. We found that the little Homunculus emits continuum radiation that can be detected at radio frequencies and that indeed represents an important contribution to the total free–free emission detected from the η Carinae nebula. 相似文献
998.
999.
A 21 cm absorption measurement over a long path length free of the effects of differential galactic rotation indicates the
existence of two distinct cloud populations in the plane. One of them consisting of cold, dense clouds has been well studied
before. The newly found hot clouds appear to be at least five times more numerous. They have a spin temperature of ~ 300 K,
an rms velocity of ~ 35 km s-1, twice the total mass, and hundred times the kinetic energy of the cold clouds. Over long path lengths, the hot clouds haveN
H/kpc ~ 2 X 1021 cm-2 Kpc-1, and are estimated to have individual column densities ≤ 1020 cm-2. We propose that they are shocked clouds found only within supernova bubbles and that the cold clouds are found in the regions
in-between old remnants, immersed in an intercloud medium. We conclude that the solar neighbourhood must be located between
old supernova remnants rather than within one. 相似文献
1000.