全文获取类型
| 收费全文 | 34677篇 |
| 免费 | 5939篇 |
| 国内免费 | 7572篇 |
专业分类
| 测绘学 | 3319篇 |
| 大气科学 | 4355篇 |
| 地球物理 | 5985篇 |
| 地质学 | 19643篇 |
| 海洋学 | 3805篇 |
| 天文学 | 3373篇 |
| 综合类 | 2265篇 |
| 自然地理 | 5443篇 |
出版年
| 2024年 | 152篇 |
| 2023年 | 430篇 |
| 2022年 | 1160篇 |
| 2021年 | 1323篇 |
| 2020年 | 1239篇 |
| 2019年 | 1622篇 |
| 2018年 | 1136篇 |
| 2017年 | 1335篇 |
| 2016年 | 1359篇 |
| 2015年 | 1520篇 |
| 2014年 | 1957篇 |
| 2013年 | 1954篇 |
| 2012年 | 2073篇 |
| 2011年 | 2208篇 |
| 2010年 | 1914篇 |
| 2009年 | 2447篇 |
| 2008年 | 2365篇 |
| 2007年 | 2418篇 |
| 2006年 | 2366篇 |
| 2005年 | 2262篇 |
| 2004年 | 1982篇 |
| 2003年 | 1881篇 |
| 2002年 | 1605篇 |
| 2001年 | 1444篇 |
| 2000年 | 1465篇 |
| 1999年 | 1267篇 |
| 1998年 | 1091篇 |
| 1997年 | 774篇 |
| 1996年 | 642篇 |
| 1995年 | 556篇 |
| 1994年 | 520篇 |
| 1993年 | 436篇 |
| 1992年 | 307篇 |
| 1991年 | 272篇 |
| 1990年 | 181篇 |
| 1989年 | 145篇 |
| 1988年 | 118篇 |
| 1987年 | 66篇 |
| 1986年 | 40篇 |
| 1985年 | 33篇 |
| 1984年 | 18篇 |
| 1983年 | 15篇 |
| 1982年 | 11篇 |
| 1981年 | 9篇 |
| 1980年 | 8篇 |
| 1979年 | 6篇 |
| 1978年 | 14篇 |
| 1977年 | 5篇 |
| 1976年 | 4篇 |
| 1954年 | 8篇 |
排序方式： 共有10000条查询结果，搜索用时 546 毫秒
141.
142.
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
143.
144.
145.
146.
147.
148.
尚永亮 《广东海洋大学学报》2003,23(2):27-29
古代荆湘之地域的特殊性使其成为朝廷贬官吏的首选之地和贬官的中转之地。在此 ,这些被贬官首创了大量关于贬谪的文学作品。其作品物色鲜明 ,楚地风情突出 ,具有近乎凝固化了的悲怨传统 ,早期逐臣、作品及谪地成为凝定的贬谪代码和符号 ,生成并积淀了深厚的人文精神。 相似文献
149.
150.
Sea‐surface temperature and salinity changes in the northwest Pacific since the Last Glacial Maximum
The oxygen isotope records of both benthic and planktonic Foraminifera in five piston cores, collected from the region between the Oyashio and Kuroshio Currents near Japan, clearly show the marked latitudinal shifts of these two currents during the past 25 kyr. Under the present hydrographic condition, a clear relationship between the sea‐surface temperature (SST) and oxygen isotope differences from benthic to planktonic Foraminifera is observed in this region. Using this relationship, we find decreased SSTs of 12–13°C (maximum 15°C) in the southernmost core site at the Last Glacial Maximum (LGM), indicating the Oyashio Current shifted southward. The SSTs at the southern two core sites abruptly increased more than 10°C at 10–11 ka, suggesting the Kuroshio Current shifted northward over these sites at 10–11 ka. In contrast, the northern two core sites have remained under the influence of the cold Oyashio Current for the past 25 kyr. With the reasonable estimate of bottom‐water temperature decrease of 2.5°C at the LGM, the SSTs estimated by this new method give exactly the same SST values calculated from Mg/Ca ratio of planktonic Foraminifera, allowing palaeosea‐surface salinities to be reconstructed. The result suggests that the ice volume effect was 1.0 ± 0.1‰ at the LGM. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献