全文获取类型
收费全文 | 3204篇 |
免费 | 873篇 |
国内免费 | 760篇 |
专业分类
测绘学 | 124篇 |
大气科学 | 88篇 |
地球物理 | 317篇 |
地质学 | 512篇 |
海洋学 | 3471篇 |
天文学 | 1篇 |
综合类 | 207篇 |
自然地理 | 117篇 |
出版年
2024年 | 20篇 |
2023年 | 83篇 |
2022年 | 120篇 |
2021年 | 127篇 |
2020年 | 143篇 |
2019年 | 148篇 |
2018年 | 108篇 |
2017年 | 132篇 |
2016年 | 133篇 |
2015年 | 151篇 |
2014年 | 247篇 |
2013年 | 186篇 |
2012年 | 246篇 |
2011年 | 237篇 |
2010年 | 189篇 |
2009年 | 241篇 |
2008年 | 213篇 |
2007年 | 162篇 |
2006年 | 182篇 |
2005年 | 142篇 |
2004年 | 143篇 |
2003年 | 132篇 |
2002年 | 152篇 |
2001年 | 117篇 |
2000年 | 94篇 |
1999年 | 80篇 |
1998年 | 116篇 |
1997年 | 96篇 |
1996年 | 98篇 |
1995年 | 89篇 |
1994年 | 101篇 |
1993年 | 85篇 |
1992年 | 76篇 |
1991年 | 73篇 |
1990年 | 49篇 |
1989年 | 76篇 |
1988年 | 5篇 |
1987年 | 7篇 |
1986年 | 12篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1974年 | 1篇 |
1964年 | 1篇 |
1963年 | 1篇 |
1962年 | 1篇 |
1941年 | 1篇 |
1935年 | 1篇 |
排序方式: 共有4837条查询结果,搜索用时 15 毫秒
1.
D.X.HU 《中国海洋湖沼学报》2004,22(3):J001-J002
Ocean circulation in the Yellow and East China Seas is very rich in mesoscale phenomena, such as eddies, fronts, upwellings, river plumes, etc. Among others, having drawn tremendous attention from oceanographic community in the past for nearly 50 years are mainly the Yellow Sea Cold Water Mass (YSCWM) and its related circulation, the Yellow Sea Warm Current (YSWC), the East China Sea 相似文献
2.
1 IntroductionBacteriaandtheiractivitiesplayanimportantroleintheelementalbiogeochemicalcyclesandenergytransformingintheocean (Zhenetal.1 997) .DortchandPackard(1 989) proposedthatfoodwebsintheeutrophicwatersaredominatedbythebiomassofprimaryproducerswhilefoodwebsintheoligotrophicwatersaredominatedbythebiomassofmicrobes.Heterotrophicbacteriahadbeenshowntoplayanimportantroleinthedecompositionoflarge ,rapidlysinkingorganicparticleswithinandbelowtheeuphot iczone ,andfurthertoaffecttheelementaldyn… 相似文献
4.
李绍全 《海洋地质与第四纪地质》1997,17(2):8-8,28
中韩合作南黄海第四纪地质对比研究之进展PROGRESSOFSINO-KOREAQUATERNARYGEOLOGICCORRELATIONSTUDYOFTHESOUTHYELLOWSEA黄海是典型的冰后期的边缘海,中韩两国共享南黄海陆架。黄海及其陆架对... 相似文献
5.
JINFeng-jun 《中国地理科学(英文版)》2003,13(2):97-103
It is very important to establish cooperative mechanism to guarantee all members to develop their e-conomies in the Yellow Sea Rim. In this paper, the development strategies ofshipplng centers and transportation networkare discussed based on economic giobalization tendency. The results argue that a united transportation network should bebuilt in order to promote the economic competition of Northeast Asia in the world. As a key component of the economiccooperation, a hierarchical shipping centers network should be established with Hong Kong, Shanghai, Pusan, Koho,and Tokyo as cores. The authorities of China, Japan, R. O. Korea and D. P. B. Korea should make more efforts tobuild a set of cooperation institutions based on raising the transportation efficiency. 相似文献
6.
Tidal effects on temperature front in the Yellow Sea 总被引:5,自引:0,他引:5
Temperature front (TF) is one of the important features in the Yellow Sea, which forms in spring, thrives in summer, and fades
in autumn as thermocline declines. TF intensity ⋎S
T
⋎ is defined to describe the distribution of TF. Based on the MASNUM wave-tide-circulation coupled model, temperature distribution
in the Yellow Sea was simulated with and without tidal effects. Along 36°N, distribution of TF from the simulated results
are compared with the observations, and a quantitative analysis is introduced to evaluate the tidal effects on the forming
and maintaining processes of the TF. Tidal mixing and the circulation structure adapting to it are the main causes of the
TF.
Supported by the National Basic Research Program of China (No. G1999043809) and the National Science Foundation of China (No.
49736190). 相似文献
7.
8.
Nine Landsat TM tapes and images and MSS images, 10 NOAA tapes and images and 1 SAR image from 1973 to 1997 were used to analyse the diffusion of suspended sediments and the change of tidal radial sand ridges in the northern part of the Changjiang River delta, the South Yellow Sea. The results showed that the diffusion of suspended sediments was controlled by the tide, net current, and submarine topography in this area. The distribution of suspended sediments had close relationship with thesubmarine topography. The old Huanghe River delta and the Changjiang River comprise the main sediment supply for the formation of radial sand ridges, whose evolution can be divided into three stages since the Huangbe River changed its course and flowed northward into the Bohai Sea. 相似文献
9.
10.
南海西部海域构造复杂,主要发育有北东—北东东向、北西向和近南北向3组深大断裂。其中,北西向断裂与板块汇聚、碰撞有关,多具走滑性质;北东—北东东向断裂具有与中国东部裂谷盆地相似的发育特点,呈张扭性质;近南北向断裂可能是南海在扩张活动期间于洋、陆壳过渡部位形成的走滑调节断裂,是洋盆扩张的西部边界。新生代里,南海经历了4次成盆事件与3期扩张活动,盆地经历了古新世—中始新世陆缘断陷、渐新世—早中新世扩展与中中新世以来的热沉降3个演化阶段。陆缘断陷阶段的充填系列主要是北东—北东东向与北西向的河流—冲积扇、湖泊沼泽等陆相沉积及火山岩等;盆地扩展阶段表现为中-小型断陷、断-坳陷逐渐复合与联合为大-中型坳陷,古地理格局逐渐由河流与湖沼陆相环境演变为滨海至浅海相的沉积环境;热沉降阶段的成盆活动逐渐减弱以至停止,地层表现超覆,盆地出现联合迹象。结合以往勘探与油气资源调查成果分析,认为南海西部海域陆架陆坡区发育的大-中型沉积盆地石油地质条件良好,蕴藏着丰富的油气资源,勘探潜力巨大。 相似文献