The relation between Zanstra temperature and morphology in planetary nebulae     

J. P. Phillips 《Monthly notices of the Royal Astronomical Society》2003,344(2):501-520

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松辽盆地中生代沉积基准面变化研究   总被引：6，自引：0，他引：6  

张世奇  任延广 《地球科学与环境学报》2003,25(2):1-5

利用地质资料研究来恢复沉积基准面变化。首先根据沉积物的分布规律、沉积构造、古生物组合及古生态、自生矿物和波基面等特征来获得古水深,然后利用对地层做脱水压实校正获得沉积物原始厚度。对湖盆地区古水深和沉积物原始厚度累加起来就可得到沉积基准面变化曲线。沉积基准面变化曲线为在松辽盆地中进行地层对比提供了依据。  相似文献   

A multicolour CCD photometric study of the open clusters NGC 2866, Pismis 19, Westerlund 2, ESO96-SC04, NGC 5617 and NGC 6204     

Giovanni Carraro  Ulisse Munari 《Monthly notices of the Royal Astronomical Society》2004,347(2):625-631

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The maximum stellar mass, star-cluster formation and composite stellar populations     

Carsten Weidner  Pavel Kroupa 《Monthly notices of the Royal Astronomical Society》2006,365(4):1333-1347

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Spatial distribution of near-infrared and optical emission properties in the bipolar nebula Menzel 3     

Nathan Smith † 《Monthly notices of the Royal Astronomical Society》2003,342(2):383-398

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Luminosity function of contact binaries based on the All Sky Automated Survey (ASAS)     

Slavek M. Rucinski 《Monthly notices of the Royal Astronomical Society》2006,368(3):1319-1322

The luminosity function for contact binary stars of the W UMa type is evaluated on the basis of the All Sky Automated Survey (ASAS) photometric project covering all stars south of  δ=+ 28°  within a magnitude range  8 < V < 13  . Lack of colour indices enforced a limitation to 3374 systems with   P < 0.562 d  (i.e. 73 per cent of all systems with   P < 1 d  ) where a simplified M_V (log  P ) calibration could be used. The spatial density relative to the main-sequence FGK stars of 0.2 per cent, as established previously from the Hipparcos sample to   V = 7.5  , is confirmed. While the numbers of contact binaries in the ASAS are large and thus the statistical uncertainties small, derivation of the luminosity function required a correction for missed systems with small amplitudes and with orbital periods longer than 0.562 d; the correction, by a factor of 3, carries an uncertainty of about 30 per cent.  相似文献   

A simple model for the evolution of disc galaxies: the Milky Way     

Thorsten Naab  Jeremiah P. Ostriker 《Monthly notices of the Royal Astronomical Society》2006,366(3):899-917

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On the self-consistency of evolutionary synthesis models     

Miguel Cerviño 《Astrophysics and Space Science》2003,284(2):897-900

Evolutionary synthesis models have been used to study the physical properties of unresolved populations in a wide range of scenarios. Unfortunately, their self-consistency is difficult to test and there are some theoretical open questions without an answer: (1) The change of the homology relations assumed in the computation of isochrones due to the effect of stellar winds (or rotation) and the discontinuities in the stellar evolution are not considered. (2) There is no consensus about how the isochrones must be integrated. (3) The discreteness of the stellar populations (that produce an intrinsic statistical dispersion) usually are not taken into account, and model results are interpreted in a deterministic way instead of a statistical one. The objective of this contribution is to present some inconsistencies in the computation and some cautions in the application of the results of such codes. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

Deep Processes of Basin Evolution:A Case Study of the Southern Songliao Basin and Adjacent Area,NE China in Mesozoic-Cenozoic     

Rihui Cheng  Dongpo Wang  Linfu Xue 《东北亚地学研究》2003,(1)

1IntroductionOne of the key factors related to basin geody-namics is deep process controlling formation and evolution of sedimentary basin. Depth and tempera-ture of asthenosphere,existence of mantle plume,occurrence of mantle melting,and amounts of melts under depressurization during thinning of lithosphere are controlling factors influenced formation and characteristics of extensional basin directly (Li,1994). Rifting is probably governed by frictional forces exerted on the base of litho…  相似文献   

Tests and constraints on theories of galaxy formation and evolution     

Rodger I. Thompson 《Astrophysics and Space Science》2003,284(2):353-356

Tests and constraints on current theories of galaxy formation and evolution are presented. They are derived from observations of the Northern Hubble Deep Field with WFPC2 and NICMOS. Photometric redshifts, extinctions and spectral energy distributions are calculated for all objects in the field. The tests and constraints are derived from the output of this analysis. The tests of the predictions from hierarchical and pure luminosity evolution galaxy evolution calculations favor the hierarchical model. Constraints are provided by the current luminosity function and its evolution to a redshift of 6. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献