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991.
Energy utilization in the aquifers is a new technology closely related to development of heat pump technique. It is significant for the flow distribution to be predicted in the aquifer surrounding the Groundwater Source Heat Pump System (GSHPS). The authors presented a new concept of "flow transfixion" by analyzing general features of aquifers, and then discussed interaction of the flow transfixion with the heat transfixion, which has practical significance to projects. A numerical model of groundwater flow was established based on the basic tenets of water-heat transferring in the aquifer. On this basis the flow field and the temperature field of GSHPS for a site in Shenyang City were numerically simulated. The basis of the flow transfixion was obtained; it was discussed for the influence of the flow transfixion on the heat transfixion. To a certain extent, the study offers some reference for the projects' design of GSHP in the studied area.  相似文献   
992.
文中总结单舰航线水文气象保障业务的特点、难点,并结合航线水文气象保障的现状提出一些个人的建设性建议。  相似文献   
993.
通过耦合布设海底表面和孔内水合物观测系统获取物理、化学、微生物等数据是了解掌握海洋水合物环境动态变化、碳循环规律和资源开发技术的有效手段,据此初步提出了一套海底孔内水合物观测系统,并指出了系统的关键技术难点。而在钻井布设该孔内观测系统时,要注意防止井内安全事故的发生,充分评估安放位置处含水合物地层的地质力学稳定性并采取适当的钻井和完井方式稳定或强化含水合物地层以支撑孔内观察仪器,实现孔内长期监测。最后讨论了在我国南海实施孔内水合物观测系统的必要性,并提出了初步想法。  相似文献   
994.
995.
胡娜  张晓林 《海洋测绘》2008,28(2):24-28
分析了伽利略搜救系统的地面站定位模型。提出了一种适用于该系统的,在存在多余观测的情况下,基于信号的时间延迟和多普勒频率测量值加权后,共同参与平差计算的联合定位算法模型及其误差分布模型。仿真结果表明,与单纯使用一种观测值的定位算法相比,该算法可以提高定位精度,是一种适合伽利略搜救地面站使用的定位算法。  相似文献   
996.
A new real-time, event-triggered storm surge prediction system has been developed for the State of North Carolina to assist emergency managers, policy-makers and other government officials with evacuation planning, decision-making and resource deployment during tropical storm landfall and flood inundation events. The North Carolina Forecast System (NCFS) was designed and built to provide a rapid response assessment of hurricane threat, accomplished by driving a high-resolution, two-dimensional, depth-integrated version of the ADCIRC (Advanced Circulation) coastal ocean model with winds from a synthetic asymmetric gradient wind vortex. These parametric winds, calculated at exact finite-element mesh node locations and directly coupled to the ocean model at every time step, are generated from National Hurricane Center (NHC) forecast advisories the moment they are inserted into the real-time weather data stream, maximizing the number of hours of forecast utility. Tidal harmonic constituents are prescribed at the open water boundaries and applied as tidal potentials in the interior of the ocean model domain. A directional surface roughness parameterization that modulates the wind speed at a given location based on the types of land cover encountered upwind, a forest canopy sheltering effect, and a spatially varying distribution of Manning’s–n friction coefficient used for computing the bottom/channel bed friction are also included in the storm surge model. Comparisons of the simulated wind speeds and phases against their real meteorological counterparts, of model elevations against actual sea surface elevations measured by NOAA tide gauges along the NC coast, and of simulated depth-averaged current velocities against Acoustic Doppler Current Profiler (ADCP) data, indicate that this new system produces remarkably realistic predictions of winds and storm surge.  相似文献   
997.
基于ERDAS的SPOT5卫星影像正射校正方法研究   总被引:2,自引:0,他引:2       下载免费PDF全文
海岛海岸带卫星遥感调查与评价项目以高分辨率卫星遥感影像数据为基础。项目区块地形有一半为山地和丘陵,地形起伏较大,常规的几何校正难以消除因地形起伏引起的影像几何变形,必须进行正射校正。根据现有数据特点和项目要求,提出了可行的正射校正流程,基于SPOT5物理模型对融合影像进行正射校正,实验校正结果完全满足精度要求。  相似文献   
998.
水生动物热休克蛋白研究进展   总被引:8,自引:2,他引:6  
由于栖息环境的特殊性,水生动物热休克蛋白的诱导及其生态意义具有不同于陆生动物的特性.本文总结了近年来水生动物热休克蛋白方面的研究进展,介绍热休克蛋白的调节机制及其功能,归纳水生动物热休克蛋白对温度、环境污染和其他因子的反应,着重分析热休克蛋白表达在水生动物中热耐受性和交叉保护中的作用,及其对水生动物分布和适合度的影响.  相似文献   
999.
Partial pressure of CO2(pCO2) was investigated in the Changjiang(Yangtze River) Estuary,Hangzhou Bay and their adjacent areas during a cruise in August 2004,China.The data show that pCO2 in surface waters of the studied area was higher than that in the atmosphere with only exception of a patch east of Zhoushan Archipelago.The pCO2 varied from 168 to 2 264 μatm,which fell in the low range compared with those of other estuaries in the world.The calculated sea-air CO2 fluxes decreased offshore and varied from -10.0 to 88.1 mmol m-2 d-1 in average of 24.4 ± 16.5 mmol m-2 d-1.Although the area studied was estimated only 2 × 104 km2,it emitted(5.9 ± 4.0) × 103 tons of carbon to the atmosphere every day.The estuaries and their plumes must be further studied for better understanding the role of coastal seas playing in the global oceanic carbon cycle.  相似文献   
1000.
This study investigates the Arctic Ocean warming episodes in the 20th century using both a high-resolution coupled global climate model and historical observations. The model, with no flux adjustment, reproduces well the Atlantic Water core temperature (AWCT) in the Arctic Ocean and shows that four largest decadalscale warming episodes occurred in the 1930s, 70s, 80s, and 90s, in agreement with the hydrographic observational data. The difference is that there was no pre-warming prior to the 1930s episode, while there were two pre-warming episodes in the 1970s and 80s prior to the 1990s, leading the 1990s into the largest and prolonged warming in the 20th century. Over the last century, the simulated heat transport via Fram Strait and the Barents Sea was estimated to be, on average, 31.32 TW and 14.82 TW, respectively, while the Bering Strait also provides 15.94 TW heat into the west- ern Arctic Ocean. Heat transport into the Arctic Ocean by the Atlantic Water via Fram Strait and the Barents Sea correlates significantly with AWCT ( C = 0.75 ) at 0- lag. The modeled North Atlantic Oscillation (NAO) index has a significant correlation with the heat transport ( C = 0.37 ). The observed AWCT has a significant correlation with both the modeled AWCT ( C =0.49) and the heat transport ( C =0.41 ). However, the modeled NAO index does not significantly correlate with either the observed AWCT ( C = 0.03 ) or modeled AWCT ( C = 0.16 ) at a zero-lag, indicating that the Arctic climate system is far more complex than expected.  相似文献   
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