全文获取类型
| 收费全文 | 7214篇 |
| 免费 | 1113篇 |
| 国内免费 | 1630篇 |
专业分类
| 测绘学 | 94篇 |
| 大气科学 | 202篇 |
| 地球物理 | 796篇 |
| 地质学 | 4586篇 |
| 海洋学 | 622篇 |
| 天文学 | 2148篇 |
| 综合类 | 317篇 |
| 自然地理 | 1192篇 |
出版年
| 2024年 | 32篇 |
| 2023年 | 106篇 |
| 2022年 | 316篇 |
| 2021年 | 322篇 |
| 2020年 | 298篇 |
| 2019年 | 328篇 |
| 2018年 | 284篇 |
| 2017年 | 274篇 |
| 2016年 | 261篇 |
| 2015年 | 314篇 |
| 2014年 | 315篇 |
| 2013年 | 371篇 |
| 2012年 | 338篇 |
| 2011年 | 348篇 |
| 2010年 | 298篇 |
| 2009年 | 551篇 |
| 2008年 | 442篇 |
| 2007年 | 489篇 |
| 2006年 | 543篇 |
| 2005年 | 409篇 |
| 2004年 | 404篇 |
| 2003年 | 450篇 |
| 2002年 | 363篇 |
| 2001年 | 305篇 |
| 2000年 | 308篇 |
| 1999年 | 258篇 |
| 1998年 | 281篇 |
| 1997年 | 189篇 |
| 1996年 | 141篇 |
| 1995年 | 126篇 |
| 1994年 | 132篇 |
| 1993年 | 84篇 |
| 1992年 | 85篇 |
| 1991年 | 44篇 |
| 1990年 | 46篇 |
| 1989年 | 26篇 |
| 1988年 | 21篇 |
| 1987年 | 22篇 |
| 1986年 | 10篇 |
| 1985年 | 3篇 |
| 1984年 | 6篇 |
| 1983年 | 3篇 |
| 1982年 | 1篇 |
| 1981年 | 4篇 |
| 1980年 | 1篇 |
| 1979年 | 1篇 |
| 1977年 | 1篇 |
| 1954年 | 3篇 |
排序方式： 共有9957条查询结果，搜索用时 93 毫秒
51.
52.
We present a new model for the chemical evolution of elliptical galaxies taking into account SN feedback, detailed nucleosynthesis
and galactic winds. We discuss the effect of galactic winds on the chemical enrichment of the ICM and compute the energy per
particle injected by the galaxies into the ICM.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
53.
Stellar population synthesis at the resolution of 2003 总被引：2，自引：0，他引：2
54.
55.
56.
This paper features the structural evolution of the eastern margin of Eurasia in Late Mesozoic and Cenozoic.It is characterized by three stages of development: the riftogenic stage (Jurassic-Early Cretaceous), the platform stage (Late Cretaceous) and the neotectonic one (Paleogene-Quarternary). The boundaries between these stages are distinctly fixed by the geological time limits of planetary range. It is demonstrated that the riftogenic and neotectonic stages were characterized by a high degree of geodynamic activity, and the platform one by a decrease in contrast of tectonic movements. The main river net was formed in the Early Cretaceous and in the Neogene. It experienced a serious reconstruction accompanied by the formation of the Amur River valley being similar to the modem one. 相似文献
57.
Guinevere Kauffmann Timothy M. Heckman Simon D. M. White Stéphane Charlot Christy Tremonti Jarle Brinchmann Gustavo Bruzual Eric W. Peng Mark Seibert Mariangela Bernardi Michael Blanton Jon Brinkmann Francisco Castander Istvan Csábai Masataka Fukugita Zeljko Ivezic Jeffrey A. Munn Robert C. Nichol Nikhil Padmanabhan Aniruddha R. Thakar David H. Weinberg Donald York 《Monthly notices of the Royal Astronomical Society》2003,341(1):33-53
58.
59.
60.
Ignacio Ferreras Alessandro Melchiorri Domenico Tocchini-Valentini 《Monthly notices of the Royal Astronomical Society》2003,344(1):257-261
The age of the Universe has been increasingly constrained by different techniques, such as the observations of type Ia supernovae (SNIa) at high redshift or dating the stellar populations of globular clusters. In this paper, we present a complementary approach using the colours of the brightest elliptical galaxies in clusters over a wide redshift range ( z ≲ 1) . We put new and independent bounds on the dark energy equation of state parametrized by a constant pressure-to-density ratio w Q and by a parameter (ξ) which determines the scaling between the matter and dark energy densities. We find that accurate estimates of the metallicities of the stellar populations in moderate and high-redshift cluster galaxies can pose stringent constraints on the parameters that describe dark energy. Our results are in good agreement with the analysis of dark energy models using SNIa data as a constraint. Accurate estimates of the metallicities of stellar populations in cluster galaxies at z ≲ 2 will make this approach a powerful complement to studies of cosmological parameters using high-redshift SNIa. 相似文献