信息量法在西宁市斜坡稳定性评价中的应用

本文选定西宁市东川弱侧丘陵前缘做为评价对象,采用二态变量信息法,对斜皮稳定性进行试评价。通过本次尝试性计算评价,与实际情况对比检验,其准确率达到８９％。故本方法在斜坡稳定性评价中较为实用。     

胜利油田火山岩单个包裹体碳同位素

近年来,在我国东部陆续发现了一些二氧化碳气藏,对其成因,不少学者有过讨论, 得出许多重要认识^①。     

Magmatic Network Structure of Volcanic Rocks in the Shengli Oilfield, Eastern China

Types of polymerized molecular network structure and degree of bond breakdown for glass phases of magmatic inclusions and glassy matrix in volcanic rocks from the Shengli oilfield have been defined by the laser Raman spectroscopic investigation. There are significant differences in types of polymerized molecular network structure and degree of bond 'breakdown of the magmatic glass phases between the non-CO2 and COa gas pools: magmatic glass phases of fluid inclusions and matrix in volcanic rocks from the CO2 gas pool contain more sheet network molecules and have a greater degree of bond beakdown than those from the non-CO2 gas pool; and when gas bubbles occur in evolving magma, magma saturated with volatile components has more sheet network molecules. The results suggest the magma-degassing mechanism of the formation of CO2 gas pools in the Shengli oilfield.     

海尔—波普彗星的CO（J=1—0）谱线的观测

使用紫金山天文台青海观测站13．7米毫米波射电望远镜,于1996年12月10日至1997年1月2日和1997年3月25日至1997年4月4日对海尔－波普彗星的CO分子J＝1—0转动跃迁谱线（频率为115．27120GHz）进行了观测．观测谱线表明,CO分子相对于地心的速度比彗星整体相对于地心的速度要小些,即有蓝移现象．这反映了CO分子是由该彗星迎着太阳的面以一定的速度产生出来的．从观测谱线中还初步估算了该彗星CO分子的产生速率．     

Red quasars not so dusty

Webster et al. claimed that up to 80 per cent of QSOs may be obscured by dust. They inferred the presence of this dust from the remarkably broad range of B − K optical–infrared colours of a sample of flat-spectrum PKS radio QSOs. If such dust is typical of QSOs, it will have rendered invisible most of those which would otherwise have been detected by optical surveys. We used the William Herschel Telescope on La Palma to obtain K infrared images of 54 B3 radio QSOs selected at low frequency (mainly steep-spectrum), and we find that although several have very red optical–infrared colours, most of these can be attributed to an excess of light in K rather than a dust-induced deficit in B. We present evidence that some of the infrared excess comes from the light of stars in the host galaxy (some, as previously suggested, comes from synchrotron radiation associated with flat-spectrum radio sources). The B − K colours of the B3 QSOs provide no evidence for a large reddened population. Either the Webster et al. QSOs are atypical in having such large extinctions, or their reddening is not due to dust; either way, the broad range of their B − K colours does not provide evidence that a large fraction of QSOs has been missed from optical surveys.     

Submillimetre-wave gravitational lenses and cosmology

One of the most direct routes for investigating the geometry of the Universe is provided by the numbers of strongly magnified gravitationally lensed galaxies as compared with those that are either weakly magnified or de-magnified. In the submillimetre waveband the relative abundance of strongly lensed galaxies is expected to be larger as compared with the optical or radio wavebands, both in the field and in clusters of galaxies. The predicted numbers depend on the properties of the population of faint galaxies in the submillimetre waveband, which was formerly very uncertain; however, recent observations of lensing clusters have reduced this uncertainty significantly and confirm that a large sample of galaxy–galaxy lenses could be detected and investigated using forthcoming facilities, including the FIRST and Planck Surveyor space missions and a large ground-based millimetre/submillimetre-wave interferometer array (MIA). We discuss how this sample could be used to impose limits on the values of cosmological parameters and the total density and form of evolution of the mass distribution of bound structures, even in the absence of detailed lens modelling for individual members of the sample. The effects of different world models on the form of the magnification bias expected in sensitive submillimetre-wave observations of clusters are also discussed, because an MIA could resolve and investigate images in clusters in detail.     

The Deutsch field gamma-ray pulsar – II. Application of the model

A new model for gamma-ray pulsars presented by Higgins & Henriksen is applied to the cases of the seven known gamma-ray pulsars. Those pulsars that are not presently observed in gamma-rays, but are candidates for observation by the next generation of gamma-ray telescopes, are discussed. The case of millisecond pulsars is discussed, and it is shown that these objects should radiate at detectable levels, in opposition to the predictions of other gamma-ray pulsar models.     

Observational limits to source confusion in the millimetre/submillimetre waveband

The first observations to detect a population of distant galaxies directly in the submillimetre waveband have recently been made using the new Submillimetre Common-User Bolometer Array (SCUBA) on the James Clerk Maxwell Telescope (JCMT). The results indicate that a large number of distant galaxies are radiating strongly in this waveband. Here we discuss their significance for source confusion in future millimetre/submillimetre-wave observations of both distant galaxies and cosmic microwave background radiation (CMBR) anisotropies. Earlier estimates of such confusion involved significant extrapolation of the results of observations of galaxies at low redshifts; our new estimates do not, as they are derived from direct observations of distant galaxies in the submillimetre waveband. The results have important consequences for the design and operation of existing and proposed millimetre/submillimetre-wave telescopes: the Planck Surveyor survey will be confusion-limited at frequencies greater than 350 GHz, even in the absence of Galactic dust emission; a 1σ confusion noise limit of about 0.44 mJy beam⁻¹ is expected for the JCMT/SCUBA at a wavelength of 850 μm; and the subarcsecond resolution of large millimetre/submillimetre-wave interferometer arrays will be required in order to execute very deep galaxy surveys.