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论述了ISO9001:2000版标准内容及采用系统工程的方法建立程序和运作过程。通过实例运作,剖析了ISO标准在煤田勘查运作中的焦点及难点和改进措施。实施ISO质量管理,对提高勘查质量和效益有战略上的意义,为煤田勘查走出国门准备了通行证。 相似文献
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陆相红层盆地1:5万区调中的遥感应用研究 总被引:3,自引:0,他引:3
本文采用遥感地质方法,对陆相红层盆地的沉积岩相、沉积体系界面、盆地充填序列、岩相变化以及地层格架影像特征进行了识别研究,取得了较好效果,为遥感在红层盆地1:5万区调中的应用,开辟了新思路。 相似文献
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Yun-Chun Jiang Yuan-Deng Shen Jing-Xiu Wang National Astronomical Observatories / Yunnan Observatory Chinese Academy of Sciences Kunming National Astronomical Observatories Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2007,7(1):129-140
1 INTRODUCTION Filaments are cool, dense material suspended in the hot, tenuous corona. It is widely accepted that the global magnetic field surrounding the filaments plays a key role in their formation, structure and stability (Tandberg-Hanssen1995). Fil… 相似文献
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Xi-Wei Liu Xiang-Dong Li 《中国天文和天体物理学报》2007,7(3):389-396
Assuming a naive star formation history, we construct synthetic X-ray source pop- ulations, using a population synthesis code, for comparison with the observed X-ray lumi- nosity function (XLF) of the interacting galaxies NGC 4038/4039. We have included high- and intermediate-mass X-ray binaries, young rotation-powered pulsars and fallback disk-fed black holes in modeling the bright X-ray sources detected. We find that the majority of the X-ray sources are likely to be intermediate-mass X-ray binaries, but for typical binary evolu- tion parameters, the predicted XLF seems to be steeper than observed. We note that the shape of the XLFs depends critically on the existence of XLF break for young populations, and suggest super-Eddington accretion luminosities or the existence of intermediate-mass black holes to account for the high luminosity end and the slope of the XLF in NGC 4038/4039. 相似文献
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Yun Xu Xin-Wu Cao Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai Graduate School of Chinese Academy of Sciences Beijing 《中国天文和天体物理学报》2007,7(1):63-70
1 INTRODUCTION Most bright active galactic nuclei (AGNs) exhibit broad emission lines, with full width at half maximum (FWHM ≥ 103 km s?1) (Peterson et al. 1999). Some type 1 AGNs could have very broad emission lines (FWHM≥ 20 000 km s?1). Type 2 AGNs s… 相似文献
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Han-Feng Song Run-Qian Huang Shao-Lan Bi 《中国天文和天体物理学报》2007,7(4):539-550
A model for contact binary systems is presented, which incorporates the following special features: a) The energy exchange between the components is based on the understand-ing that the energy exchange is due to the release of potential, kinetic and thermal energies of the exchanged mass. b) A special form of mass and angular momentum loss occurring in contact binaries is losses via the outer Lagrangian point. c) The effects of spin, orbital rota-tion and tidal action on the stellar structure as well as the effect of meridian circulation on the mixing of the chemical elements are considered. d) The model is valid not only for low-mass contact binaries but also for high-mass contact binaries. For illustration, we used the model to trace the evolution of a massive binary system consisting of one 12M and one 5M star. The result shows that the start and end of the contact stage fall within the semi-detached phase during which the primary continually transfers mass to the secondary. The time span of the contact stage is short and the mass transfer rate is very large. Therefore, the contact stage can be regarded as a special part of the semi-detached phase with a large mass transfer rate. Both mass loss through the outer Lagrangian point and oscillation between contact and semi-contact states can occur during the contact phase, and the effective temperatures of the primary and the secondary are almost equal. 相似文献
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Gui-Ping Wu Guang-Li Huang Yu-Hua Tang Yu Dai Department of Physics Southeast University Nanjing Purple Mountain Observatory Chinese Academy of Sciences Nanjing Department of Astronomy Nanjing University Nanjing 《中国天文和天体物理学报》2007,7(1):141-147
1INTRODUCTIONEnrichment of3He and heavy ions(i.e.,Ne,Mg,Si and Fe),characteristic of impulsive?ares,have beenstudied for more than three decades.It is found that they are generally associated with nonthermal energeticelectron-rich events(Reames et al.1988;Reames1999and references therein;Ho et al.2001;Wang et al.2006)and are related to the peculiar ratio of charge to mass(Mazur et al.1996;Reames1999).Althoughthe abundance of3He ions is not correlated with the abundance of heavy ions,s… 相似文献