全文获取类型
收费全文 | 477篇 |
免费 | 11篇 |
国内免费 | 1篇 |
专业分类
测绘学 | 10篇 |
大气科学 | 24篇 |
地球物理 | 110篇 |
地质学 | 85篇 |
海洋学 | 53篇 |
天文学 | 143篇 |
自然地理 | 64篇 |
出版年
2021年 | 5篇 |
2019年 | 4篇 |
2018年 | 8篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 7篇 |
2014年 | 6篇 |
2013年 | 23篇 |
2012年 | 11篇 |
2011年 | 13篇 |
2010年 | 15篇 |
2009年 | 16篇 |
2008年 | 15篇 |
2007年 | 15篇 |
2006年 | 13篇 |
2005年 | 20篇 |
2004年 | 15篇 |
2003年 | 19篇 |
2002年 | 16篇 |
2001年 | 13篇 |
2000年 | 14篇 |
1999年 | 6篇 |
1998年 | 5篇 |
1997年 | 8篇 |
1996年 | 9篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 5篇 |
1990年 | 5篇 |
1989年 | 7篇 |
1988年 | 5篇 |
1987年 | 4篇 |
1986年 | 4篇 |
1985年 | 12篇 |
1984年 | 13篇 |
1983年 | 12篇 |
1982年 | 6篇 |
1981年 | 12篇 |
1980年 | 4篇 |
1979年 | 6篇 |
1978年 | 8篇 |
1977年 | 12篇 |
1976年 | 10篇 |
1975年 | 9篇 |
1974年 | 6篇 |
1973年 | 3篇 |
1972年 | 4篇 |
1970年 | 4篇 |
1965年 | 3篇 |
排序方式: 共有489条查询结果,搜索用时 15 毫秒
301.
302.
303.
304.
A high-resolution, regional, numerical-model-based, real-time ocean prediction system for the northern South China Sea, called the Northern South China Sea Nowcast/Forecast System (NSCSNFS), has been used to investigate subtidal mesoscale flows during the time period of the Asian Seas International Acoustic Experiment (ASIAEX) field programs. The dynamics are dominated by three influences; 1) surface wind stress, 2) intrusions of the Kuroshio through Luzon Strait, and 3) the large-scale cyclonic gyre that occupies much of the northern South China Sea. Each component primarily drives currents in the upper ocean, so deep currents are rather weak. Wind stress is especially effective at forcing currents over the shallow China shelf. The Kuroshio intrusion tends to flow westward until it meets the northern edge of the large-scale cyclonic gyre. Together, these currents produce an intense, narrow jet directed northwest toward the continental slope, often in the region of the ASIAEX field programs. Upon reaching the slope, the current splits with part flowing northeastward along the slope and part flowing southwestward, producing large horizontal and vertical shears and making this region dynamically very complicated and difficult to simulate. The Kuroshio intrusion tends to be stronger (weaker) when the northeasterly winds are strong (weak) and the large-scale gyre is farther south (north), consistent with conclusions from previous model studies. At the northern boundary, the model produces a persistent northward flow through Taiwan Strait into the East China Sea. Data assimilation in the NSCSNFS model is shown to dampen the system, extracting energy and causing the entire system to spin down. 相似文献
305.
C. P. Hurkett J. P. Osborne K. L. Page E. Rol M. R. Goad P. T. O'Brien A. Beardmore O. Godet D. N. Burrows N. R. Tanvir A. Levan B. Zhang D. Malesani J. E. Hill J. A. Kennea R. Chapman V. La Parola M. Perri P. Romano R. Smith N. Gehrels 《Monthly notices of the Royal Astronomical Society》2006,368(3):1101-1109
306.
307.
T. Takagi A. M. J. Mortier K. Shimasaku K. Coppin A. Pope R. J. Ivison H. Hanami S. Serjeant D. L. Clements R. S. Priddey J. S. Dunlop T. Takata I. Aretxaga S. C. Chapman S. A. Eales D. Farrah G. L. Granato M. Halpern D. H. Hughes E. van Kampen D. Scott K. Sekiguchi I. Smail M. Vaccari 《Monthly notices of the Royal Astronomical Society》2007,381(3):1154-1168
308.
309.
Martin Cohen Jessica M. Chapman Rachel M. Deacon † Robert J. Sault Quentin A. Parker Anne J. Green 《Monthly notices of the Royal Astronomical Society》2006,369(1):189-196
We present radio observations of the unique, recently formed, planetary nebula (PN) associated with a very long-period OH/IR variable star V1018 Sco that is unequivocally still in its asymptotic giant branch phase. Two regions within the optical nebula are clearly detected in non-thermal radio continuum emission, with radio spectral indices comparable to those seen in colliding-wind Wolf–Rayet binaries. We suggest that these represent shocked interactions between the hot, fast stellar wind and the cold nebular shell that represents the PN's slow wind moving away from the central star. This same interface produces both synchrotron radio continuum and the optical PN emission. The fast wind is neither spherical in geometry nor aligned with any obvious optical or radio axis. We also report the detection of transient H2 O maser emission in this nebula. 相似文献
310.