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471.
Chen Junren Li Tinghuan Guangzhou Marine Geological Survey MGMR Guangzhou Jiang Minxi 《《地质学报》英文版》1993,67(3)
Various types of geological hazards exist in the South China Sea. In dynamics sense, they can be categorized into 5 principal genetic types related to effects of hydraulic dynamics, gaseous activity, soil mechanics, gravity and tectonism, respectively. Integrated analyses indicate that the geological hazards associated with volcanoes, earthquakes and fractures are mainly distributed in tectonically active regions, whereas those resulting from mudflows, landslides and diapirs are usually concentrated in the region of slope, that shallow gas, high pressure gas pockets and soft intercalations are major potential geological hazards in the inner shelf, and that strong hydraulic dynamics, especially storm tide, is one of the major causes of geological hazards in the littoral areas. The geological hazards that occurred in the South China Sea are also characterized by periodicity, succession and, to a certain extent, unpredictability in addition to regionalization. 相似文献
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本文以世界海相碳酸盐岩油气田为借鉴,论述了下扬子区中、古生界海相碳酸盐岩油气地质特点,进而指出了下扬子区油气前景和油气勘探领域。 相似文献
474.
SUN Yao ZHENG Bing ZHANG Bo TANG Qisheng . Key Laboratory for Sustainable Utilization of Marine Fisheries Resources of Ministry of Agriculture Yellow Sea Fisheries Research Institute Chinese Academy of Fisheries Sciences Qingdao China 《海洋学报(英文版)》2007,(3)
In the Maidao Ecological Laboratory of the Huanghai Sea Fisheries Research Institute in 1998~2000, the continuous flow-through method was adopted to determine the energy budget components and models of Schlegel’s black rockfish under different ecological and environmental factors, such as temperature, food species, body mass and feeding level, etc. The body mass of test fish ranged from 21.2 to 224.5 g. The specific growth rate tended to invert "U" change with temperature increase. The ecological conversion efficiency showed the same trend as temperature and feeding level rise. Only the specific growth rate tended to decelerate the increment with the rise of feeding level. From the above quantitative relationships, the maximum and optimal growth temperatures could be obtained as 17.5 and 16.2 ℃, and the maintenance feeding rate and optimum feeding rate as 0.8% and 4.1% of the body mass. The specific growth rate and ecological conversion coefficient showed a decelerating decrease trend with body mass increment. The small-sized fish food was more advantageous to the feeding level increase in comparison with the small-sized shrimp food, which led to the increase of growth, metabolism and excretion, but had no significant influence on the ecological conversion coefficient. All of temperature, feeding level, body mass and food species can obviously change the energy budget models. The assigning rate of growth energy tended to change along the invert "U" curve with the increase of temperature and feeding level, and decrease with the body mass increase, but the assigning rates of metabolism energy and excretion energy were quite reverse. These relationships could be quantitatively described as quadratic or power function curve. If the above relationships proved true to other marine fish, the establishment of energy budget model of the same fish under different conditions can be largely simplified. 相似文献
475.
YU Ziniu WEI Xiaohua KONG Xiaoyu YU Shanshan. Laboratory of Applied Marine Biology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou China. Key Laboratory of Mariculture of Ministry of Education Ocean University of China Qingdao China 《海洋学报(英文版)》2007,(1)
1 IntroductionFarrer’s scallopChlamys farreriis a nativescallop species occurring along the northern coast ofChina, the Democratic People’s Republic of Korea(DPRK), Korea and Japan (Wang et al., 1993).It has been one of the major species in scallop aqua… 相似文献
476.
Permeability Heterogeneity in a Fractured Sandstone–Mudstone Rock Mass in Xiaolangdi Dam Site, Central China 总被引:1,自引:0,他引:1
JIANG Xiaowei WAN Li WANG Xusheng KANG Aibin HUANG Jun and HUANG Guoxing 《《地质学报》英文版》2009,83(5):962-970
Abstract: Heterogeneity of permeability in fractured media is a hot research topic in hydrogeology. Numerous approaches have been proposed to characterize heterogeneity in the last several decades. However, little attention has been paid to correlate permeability heterogeneity with geological information. In the present study, several causes of permeability heterogeneity, that is, lithology, tectonism, and depth, are identified. The unit absorption values (denoted as ω), which are results obtained from the packer test, are employed to represent permeability. The variability of permeability in sandstone–mudstone is so significant that the value of unit absorptions span 3–4 orders of magnitude at any depth with several test sections. By declustering, it has been found that under a similar tectonic history, the means of permeability differ greatly at different formations as a result of different mudrock contents. It has also been found that in the same formation, permeability can be significantly increased as a result of faulting. The well-known phenomenon, the decrease in permeability with depth, is found to be caused by the fractures in the rock mass, and the relationship between permeability and depth can be established in the form of logω–logd. After subtracting the trend of ω with absolute depth, the mean of the residual value at each relative depth can be well correlated with the distribution of mudstone. The methods proposed in this paper can be utilized to research in similar study areas. 相似文献
477.
万安盆地位于万安断裂西侧, 是一个大型的走滑拉张盆地.其中部坳陷为富生烃坳陷, 发育有渐新统湖沼相、海湾相泥岩和下中新统浅海相泥岩2套主要烃源岩, 渐新统烃源岩具有良好的生烃潜力, 下中新统烃源岩次之.万安盆地的油气藏主要分布于中部坳陷及其相邻的西北断阶带、北部隆起和中部隆起, 而在北部坳陷、南部坳陷和东部隆起上仅见油气显示.研究表明, 万安盆地这种油气分布特征明显地受中部富生烃坳陷所控制. 相似文献
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