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221.
吕康林  唐依民 《中国岩溶》1991,10(4):319-326
松宜矿区九对矿井中的四对最大涌水量超过5000m~3/h,矿井之间水力联系密切,明显处于同一地下水系统之中。本文以防治水为目的,应用系统理论对该区地下水系统进行了分析,建立了地下水系统概化模型、防治水优化管理模型,绘制了地下水系统网络图及相应的防治水网络图。文中强调了地下水系统的整体性、层次性、目的性及相互联系。   相似文献   
222.
富钴锰结壳分析技术评介   总被引:2,自引:1,他引:2  
简要评介了用于富钴锰结壳成分分析的现代分析技术,包括船上现场分析、陆上实验室的多元素分析、矿物微区分析和元素微区分布特征研究的微探针方法及相关标准物质的研制。讨论了结壳品位分析时的取样问题及干基温度的确定和对“绿色”分析技术的需求。  相似文献   
223.
对市场上出现的盔犀鸟头胄工艺品及其拼合制品、仿制品,在宝石显微镜下放大观察,采用扫描电子显微镜、傅里叶变换红外光谱仪、紫外一可见光谱仪、激光拉曼光谱仪等大型分析仪器进行测试,探究其物质组成、生长结构、颜色成因以及鉴定方法。结果表明,盔犀鸟头胄整体表现为层状鳞片生长结构,头胄工艺品的黄色基体中普遍发育近平行条带生长结构,红色圆斑与黄色基体呈渐变过渡关系;红外光谱表现为酰胺特征吸收谱带,表明角蛋白为头胄主要成分;特征的紫外一可见吸收光谱与拉曼光谱均标志着类胡萝卜素的存在,且类胡萝卜素是头胄的主要呈色原因。拼合工艺品的红色圆斑具有清晰边界并可见拼合缝隙,红外光谱显示红色圆斑为人造树脂材料。仿制品的黄色基体内部可见气泡,红外光谱揭示其整体均为人造树脂。  相似文献   
224.
蓝闪片岩产于一套含放射虫硅质岩、硅质大理岩、板岩、变质基性火山岩中,与此相伴的超基性岩块,以一系列向南逆冲的断片产出。蓝闪片岩中的蓝闪石往往和黑硬绿泥石、钠长石、绿泥石以及钠钙闪石(蓝透闪石、冻蓝闪石等)、钙闪石(阳起石等)共存。据钠角闪石、绿泥石计算的生成压力是0.65GPa至0.8GPa,略大于美国佛兰西斯科的瓦尔德溪蓝片岩中该矿物对生成的压力。稀土元素分析证明蓝片岩的原岩是典型洋底(中脊)玄武岩和岛弧玄武岩,这是蓝片岩沟-弧俯冲-碰撞的证据之一。  相似文献   
225.
中国暴雨的科学与预报:改革开放40年研究成果   总被引:9,自引:4,他引:9  
总结了改革开放以来中国学者在暴雨科学与预报领域取得的重要研究进展和主要成果。其中,暴雨机理研究成果从重要天气系统、中国主要区域的暴雨、台风暴雨等3个方面分别进行综述,而暴雨预报技术研发与应用则从中国数值天气预报发展和暴雨预报客观方法两方面进行归纳。   相似文献   
226.
Observations indicate a surface cooling trend during the East Asian summer in recent decades, against a background of global warming. This cooling trend is re-examined using station data from 1951 to 2007, and atmospheric general circulation model (AGCM) simulations are performed to investigate the possible influence of changes in external forcing. The numerical experiments are designed to investigate the effects of four types of external forcing: greenhouse gases (GHGs), Total Solar Irradiance (TSI), ozone, and the direct effects of aerosols. Results indicate that external forcing contributes to the cooling trend over East Asia. Furthermore, GHGs, and to a lesser degree the direct effects of aerosols, are the main contributors to the cooling trend. The possible linkages between the external forcings and the cooling trend are discussed.  相似文献   
227.
利用资料诊断和全球大气原始方程模式(Intermediate General Circulation Model,IGCM),研究了2008年1月中国南方地区出现罕见的持续性雨雪事件的成因.结果表明,2008年1月大气非绝热加热场的主要异常出现在热带海洋、青藏高原及中亚地区以及北大西洋.用全球异常热源强迫IGCM得到的...  相似文献   
228.
Numerical experiments with different idealized land and mountain distributions are carried out to study the formation of the Asian monsoon and related coupling processes. Results demonstrate that when there is only extratropical continent located between 0 and 120°E and between 20/30°N and the North Pole, a rather weak monsoon rainband appears along the southern border of the continent, coexisting with an intense intertropical convergence zone (ITCZ). The continuous ITCZ surrounds the whole globe, prohibits the development of near-surface cross-equatorial flow, and collects water vapor from tropical oceans, resulting in very weak monsoon rainfall. When tropical lands are integrated, the ITCZ over the longitude domain where the extratropical continent exists disappears as a consequence of the development of a strong surface cross-equatorial flow from the winter hemisphere to the summer hemisphere. In addition, an intense interaction between the two hemispheres develops, tropical water vapor is transported to the subtropics by the enhanced poleward flow, and a prototype of the Asian monsoon appears. The Tibetan Plateau acts to enhance the coupling between the lower and upper tropospheric circulations and between the subtropical and tropical monsoon circulations, resulting in an intensification of the East Asian summer monsoon and a weakening of the South Asian summer monsoon. Linking the Iranian Plateau to the Tibetan Plateau substantially reduces the precipitation over Africa and increases the precipitation over the Arabian Sea and the northern Indian subcontinent, effectively contributing to the development of the South Asian summer monsoon.  相似文献   
229.
The Flexible Global Ocean-Atmosphere-Land System model, Spectral Version 2 (FGOALS-s2) was used to simulate realistic climates and to study anthropogenic influences on climate change. Specifically, the FGOALS-s2 was integrated with Coupled Model Intercomparison Project Phase 5 (CMIP5) to conduct coordinated experiments that will provide valuable scientific information to climate research communities. The performances of FGOALS-s2 were assessed in simulating major climate phenomena, and documented both the strengths and weaknesses of the model. The results indicate that FGOALS-s2 successfully overcomes climate drift, and realistically models global and regional climate characteristics, including SST, precipitation, and atmospheric circulation. In particular, the model accurately captures annual and semi-annual SST cycles in the equatorial Pacific Ocean, and the main characteristic features of the Asian summer monsoon, which include a low-level southwestern jet and five monsoon rainfall centers. The simulated climate variability was further examined in terms of teleconnections, leading modes of global SST (namely, ENSO), Pacific Decadal Oscillations (PDO), and changes in 19th–20th century climate. The analysis demonstrates that FGOALS-s2 realistically simulates extra-tropical teleconnection patterns of large-scale climate, and irregular ENSO periods. The model gives fairly reasonable reconstructions of spatial patterns of PDO and global monsoon changes in the 20th century. However, because the indirect effects of aerosols are not included in the model, the simulated global temperature change during the period 1850–2005 is greater than the observed warming, by 0.6°C. Some other shortcomings of the model are also noted.  相似文献   
230.
Large-ensemble simulations of the atmosphere-only time-slice experiments for the Polar Amplification Model Intercomparison Project (PAMIP) were carried out by the model group of the Chinese Academy of Sciences (CAS) Flexible Global Ocean-Atmosphere-Land System (FGOALS-f3-L). Eight groups of experiments forced by different combinations of the sea surface temperature (SST) and sea ice concentration (SIC) for pre-industrial, present-day, and future conditions were performed and published. The time-lag method was used to generate the 100 ensemble members, with each member integrating from 1 April 2000 to 30 June 2001 and the first two months as the spin-up period. The basic model responses of the surface air temperature (SAT) and precipitation were documented. The results indicate that Arctic amplification is mainly caused by Arctic SIC forcing changes. The SAT responses to the Arctic SIC decrease alone show an obvious increase over high latitudes, which is similar to the results from the combined forcing of SST and SIC. However, the change in global precipitation is dominated by the changes in the global SST rather than SIC, partly because tropical precipitation is mainly driven by local SST changes. The uncertainty of the model responses was also investigated through the analysis of the large-ensemble members. The relative roles of SST and SIC, together with their combined influence on Arctic amplification, are also discussed. All of these model datasets will contribute to PAMIP multi-model analysis and improve the understanding of polar amplification.  相似文献   
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