首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   34811篇
  免费   541篇
  国内免费   321篇
测绘学   706篇
大气科学   2264篇
地球物理   6835篇
地质学   12965篇
海洋学   3285篇
天文学   7323篇
综合类   110篇
自然地理   2185篇
  2022年   907篇
  2021年   1268篇
  2020年   1195篇
  2019年   1271篇
  2018年   933篇
  2017年   710篇
  2016年   630篇
  2015年   499篇
  2014年   626篇
  2013年   1335篇
  2012年   793篇
  2011年   1207篇
  2010年   1038篇
  2009年   1455篇
  2008年   1136篇
  2007年   1154篇
  2006年   1066篇
  2005年   888篇
  2004年   1065篇
  2003年   1132篇
  2002年   1084篇
  2001年   959篇
  2000年   813篇
  1999年   723篇
  1998年   772篇
  1997年   820篇
  1996年   471篇
  1995年   452篇
  1994年   454篇
  1993年   367篇
  1992年   367篇
  1991年   340篇
  1990年   354篇
  1989年   341篇
  1988年   289篇
  1987年   353篇
  1986年   364篇
  1985年   398篇
  1984年   438篇
  1983年   441篇
  1982年   348篇
  1981年   351篇
  1980年   340篇
  1979年   293篇
  1978年   333篇
  1977年   285篇
  1976年   277篇
  1975年   299篇
  1974年   302篇
  1973年   284篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Afanasyev  D. F.  Akatov  V. V. 《Oceanology》2021,61(2):244-253
Oceanology - Field observations were applied to study the macrophytobenthos of the Abrau Peninsula of the Black Sea and the effect of the two most common and largest species of brown algae of the...  相似文献   
2.
Kopylov  A. I.  Kosolapov  D. B.  Zabotkina  E. A.  Romanenko  A. V.  Sazhin  A. F. 《Oceanology》2021,61(2):220-232
Oceanology - The distribution of heterotrophic bacteria, viruses, and heterotrophic nanoflagellates was studied in the shelf waters of the East Siberian Sea along the meridional transect from the...  相似文献   
3.
Shakirov  R. B.  Cuong  Do Huy  Obzhirov  A. I.  Valitov  M. G.  Lee  N. S.  Legkodimov  A. A.  Kalgin  V. Yu.  Yeskova  A. I.  Proshkina  Z. N.  Telegin  Yu. A.  Storozhenko  A. V.  Ivanov  M. V.  Pletnev  S. P.  Sedin  V. T.  Bulanov  A.V.  Shvalov  D. A.  Lipinskaya  N. A.  Bovsun  M. A.  Makseev  D. S.  Thanh  Nguyen Trung  Anh  Le Duc  Luong  Le Duc 《Oceanology》2021,61(1):147-149
Oceanology - Abstract—The paper gives brief results of comprehensive studies in the South China Sea obtained from a joint Russian–Vietnamese expedition in November 2019 (cruise 88 of...  相似文献   
4.
Izvestiya, Atmospheric and Oceanic Physics - A comparative analysis of high time resolution data acquired by the SEVIRI scanner and temperature-profiling drifters during a multiyear period is...  相似文献   
5.
Geomagnetism and Aeronomy - The total electron content (TEC) data obtained from the ground-based GPS receiver stations of the Nigerian GNSS network of stations (NIGNET) have been used in this study...  相似文献   
6.
Water Resources - The factors of phytoplankton development in the stratified Mozhaisk Reservoir are analyzed on the basis of long-term observations and model calculations. To analyze the...  相似文献   
7.
Surveys in Geophysics - Over the last 15 years, the satellite constellation of the global positioning system (GPS) has been modernized for more precise applications, with the introduction...  相似文献   
8.
Orlov  A. M.  Gorbatenko  K. M.  Benzik  A. N.  Rybakov  M. O.  Nosov  M. A.  Orlova  S. Yu. 《Oceanology》2021,61(2):295-296
Oceanology - The article presents the results of hydrobiological, ichthyological, trophological, acoustic, and genetic research aboard the R/V Professor Levanidov in the Chukchi, East Siberian,...  相似文献   
9.
Multiscale simulation of fluvio‐deltaic stratigraphy was used to quantify the elements of the geometry and architectural arrangement of sub‐seismic‐scale fluvial‐to‐shelf sedimentary segments. We conducted numerical experiments of fluvio‐deltaic system evolution by simulating the accommodation‐to‐sediment‐supply (A/S) cycles of varying wavelength and amplitude with the objective to produce synthetic 3‐D stratigraphic records. Post‐processing routines were developed in order to investigate delta lobe architecture in relation to channel‐network evolution throughout A/S cycles, estimate net sediment accumulation rates in 3‐D space, and extract chronostratigraphically constrained lithosomes (or chronosomes) to quantify large‐scale connectivity, that is, the spatial distribution of high net‐to‐gross lithologies. Chronosomes formed under the conditions of channel‐belt aggradation are separated by laterally continuous abandonment surfaces associated with major avulsions and delta‐lobe switches. Chronosomes corresponding to periods in which sea level drops below the inherited shelf break, that is, the youngest portions of the late falling stage systems tract (FSST), form in the virtual absence of major avulsions, owing to the incision in their upstream parts, and thus display purely degradational architecture. Detailed investigation of chronosomes within the late FSST showed that their spatial continuity may be disrupted by higher‐frequency A/S cycles to produce “stranded” sand‐rich bodies encased in shales. Chronosomes formed during early and late falling stage (FSST) demonstrate the highest large‐scale connectivity in their proximal and distal areas, respectively. Lower‐amplitude base level changes, representative of greenhouse periods during which the shelf break is not exposed, increase the magnitude of delta‐lobe switching and favour the development of system‐wide abandonment surfaces, whose expression in real‐world stratigraphy is likely to reflect the intertwined effects of high‐frequency allogenic forcing and differential subsidence.  相似文献   
10.
Deinego  I. D.  Ansorge  I.  Belyaev  K. P. 《Oceanology》2021,61(5):613-624
Oceanology - The data assimilation (DA) of satellite observations of the ocean level from the Archiving Validating and Interpolating Satellite Observations (AVISO) into the IWM model (G.I. Marchuk...  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号