全文获取类型
收费全文 | 173篇 |
免费 | 28篇 |
国内免费 | 39篇 |
专业分类
测绘学 | 45篇 |
大气科学 | 21篇 |
地球物理 | 18篇 |
地质学 | 104篇 |
海洋学 | 24篇 |
天文学 | 2篇 |
综合类 | 18篇 |
自然地理 | 8篇 |
出版年
2024年 | 1篇 |
2023年 | 8篇 |
2022年 | 2篇 |
2021年 | 5篇 |
2020年 | 4篇 |
2019年 | 11篇 |
2018年 | 9篇 |
2017年 | 5篇 |
2016年 | 7篇 |
2015年 | 7篇 |
2014年 | 11篇 |
2013年 | 13篇 |
2012年 | 15篇 |
2011年 | 10篇 |
2010年 | 9篇 |
2009年 | 10篇 |
2008年 | 13篇 |
2007年 | 9篇 |
2006年 | 6篇 |
2005年 | 10篇 |
2004年 | 9篇 |
2003年 | 4篇 |
2002年 | 5篇 |
2001年 | 1篇 |
2000年 | 4篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1994年 | 1篇 |
1993年 | 8篇 |
1992年 | 3篇 |
1991年 | 24篇 |
1990年 | 1篇 |
1988年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1964年 | 2篇 |
排序方式: 共有240条查询结果,搜索用时 296 毫秒
1.
2.
The use of lysosomal stability in the mussel, Mytilus galloprovincialis, as a potential biomarker of environmental contamination has been evaluated along the Portuguese coast. To this end, the neutral red retention (NRR) time was measured in mussel haemocytes gathered from nine different locations reflecting different degrees of anthropogenic contamination. Mussels collected in the vicinity of industrial and urban areas showed the lowest lysosomal stability. Additionally, no significant seasonal variability (winter-spring/summer) for NRR time was observed. In order to further support the usefulness of this method as an integrated tool for monitoring marine coastal environments, we compared the levels of xenobiotics in mussel tissues with the obtained NRR values. The results highlighted a consistent pattern, with the lowest lysosomal stability intimately correlated with the higher contaminant concentrations. In summary, this integrated approach further demonstrated that the NRR assay can provide useful and objective indications of the real health status of organisms subjected to different stress agents, being a valid option for environmental monitoring. 相似文献
3.
浅谈城市地下管线普查成果数据的质量检查 总被引:1,自引:0,他引:1
本文阐述了对城市地下管线普查成果数据进行质量检查的必要性,并结合工作实际,介绍了质量检查的内容和方法. 相似文献
4.
5.
6.
7.
Yin Xiulan China Institute of Geo-environmental Monitoring Beijing China Hu Ping Faculty of Earth Sciences China University of Geosciences Wuhan China Northeastern Illinois University Chicago IL USA Li Dien Division of Earth Environmental Sciences Los Alamos National Laboratory Los Alamos NM USA 《中国地质大学学报(英文版)》2004,15(4):355-360
The sorption of Eu species onto nano-size silica-water interfaces was investigated using fluorescence spectroscopy for Ph ranges of 1-8.5 and an initial Eu concentration (Ceu) of 2×10-4 M. The sorption rate of Eu was initially low, but significantly increased at Ph>4. The sorption density of Eu species on a silica surface was ~1.58×10-7 mol/m2 when the dissolved Eu species were completely sorbed onto silica-water interfaces at Ph=~5.8. The sorbed Eu species at Ph<6 is aquo Eu3 , which is sorbed onto silica-water interfaces as an outer-sphere complex at Ph<5, but may be sorbed as an inner-sphere bidentate complex at 5相似文献
8.
HU Ping YIN Xiulan ZHAO Linghu & LI Dien . Department of Earth Sciences China University of Geosciences Wuhan China . Northeastern Illinois University Chicago IL USA . China Institute of Geo-Environmental Monitoring Beijing China . Division of Chemistry Los Alamos National Laboratory Los Alamos NM USA 《中国科学D辑(英文版)》2005,48(11)
A large amount of nuclear wastes has been pro-duced due to nuclear weapon development and nuclear electricity generation. One possible resolution for the disposal of the nuclear wastes is to seal them in an underground repository, which requires detailed knowledge on the mobility, chemical behavior and immobilization of radionuclides in underground water. In addition, toxic heavy metals are extensively present in ground and underground water, how to immobilize and remedy these toxic heavy meta… 相似文献
9.
10.
本文利用中尺度数值模式WRF和LAGRANTO轨迹模式对2010年变性台风"Malakas"进行数值模拟和轨迹分析,分析了Malakas在变性过程中与中纬度系统的相互作用,以及在相互作用过程中Malakas的结构变化特征。结果表明:Malakas变性过程经历了三个阶段:(1)高层扰动加强期,高层的正位涡产生的气旋性环流使低层Malakas中心北部的斜压带西侧产生负的温度平流,表现为冷空气的入侵;(2)Malakas和中纬度系统相互作用时期,台风北上导致斜压带出现,深对流的爆发使低层暖湿气流沿着斜压带上升,快速上升气流中的潜热释放导致低PV空气向对流层上部净输送,在其北部高层重新构建出一个脊;(3)Malakas变性成温带气旋,残存的台风内核与斜压带逐渐合并,负的位涡平流带着非绝热外出流驱动了下游最初脊的构建,加速并且固定了中纬度急流,并整体放大了上层Rossby波模式。 相似文献