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41.
The future development of new-type urbanization has drawn great attention from both the government and public alike. In this context, the present study had three related research aims. Firstly, it sought to predict the urbanization and population dynamics in China at both national and provincial levels for the period of 2015 to 2030. Secondly, on this basis, it sought to examine the spatial variation of urbanization given the predicted national urbanization rate of 70.12%. Thirdly, it sought to estimate and evaluate the national and provincial demands of investment in the development of new-type urbanization. The main conclusions from this study were as follows: (1) The population size and urbanization rate will reach 1.445 billion and 70.12%, respectively, from 2015 to 2030. (2) The demographic dividend will vanish when the population pressure reaches its maximum. During this period, there will be 70.16 million urban population born. The suburban population that becomes urbanized will be 316.7 million, and thus the net increase in urban population will reach 386 million. (3) Although the urbanization rate of every Chinese province will increase during 2015–2030, it will do so unequally, while differences in urbanization quality among provinces will also be substantial. In some provinces, moreover, the urbanization quality is not compatible with their eco-social development. (4) A total of 4,105,380 billion yuan is required to fund new-type urbanization and the investment demand for each province varies greatly; for example, Guangdong province requires the most funding, amounting to approximately 148 times that required by Tibet, the province in least need of funding. In the final part of this study, policy suggestions concerning the investment of the new-type urbanization are put forward and discussed.  相似文献   
42.
SEED格式STEIM2数据压缩算法在实时地震数据传输中的应用   总被引:8,自引:1,他引:8  
在一定带宽内,及时、高效、无失真地传输地震数据是地震数据传输的基本要求,SEED格式给出的数据格式在数据压缩方面有其独到之处,但SEED格式没有定义数据正确性和完整性保证机制和检验方法,因而影响实时传输中的使用。本文提出一种基于SEED格式的STEIM2数据压缩算法,同EDAS数据包形式兼容的实时压缩数据包编码方法,来实现实时压缩数据的传输。经理论评估和实际数据检验,它容易实现,效率高,安全,可靠,完全可以应用于实时数据传输。  相似文献   
43.
44.
????CNES???????????????????λ???????д?????????????????о????????????????????????????????????????????????CNES??????????????????SuomiNet????????????????IGS??????????????????????????????????????????????????к???????  相似文献   
45.
Macroalgae plays an important role in coastal ecosystems. The accurate delineation of macroalgae areas is important for environmental management. This study compared the pixel- and object-based methods using Gaofen satellite no. 2 image to explore an efficient classification approach. Expert system rules and nearest neighbour classifier were adopted for object-based classification, whereas maximum likelihood classifier was implemented in the pixel-based approach. Normalized difference vegetation index, normalized difference water index, mean value of the blue band and geometric characteristics were selected as features to distinguish macroalgae farms by considering the spectral and spatial characteristics. Results show that the object-based method achieved a higher overall accuracy and kappa coefficient than the pixel-based method. Moreover, the object-based approach displayed superiority in identifying Porphyra class. These findings suggest that the object-based method can delineate macroalgae farming areas efficiently and be applied in the future to monitor the macroalgae farms with high spatial resolution imagery.  相似文献   
46.
从山东省地震局数字信息服务的沿革、数字科技信息网的建设、及对数字化信息资源建设与服务的再认识等方面,展示了山东省地震局数字科技信息服务平台。该平台突出防震减灾和地区特色,整合信息资源,建立了更加完备的数字化信息网站,全面提升了山东省地震局数字科技信息的服务水平,以全新的服务模式实现了全方位、多层次的数字化信息管理服务。  相似文献   
47.
The Lanhualing tungsten-molybdenum deposit is a skarn-type deposit located in Ningguo county, Anhui province. This deposit is mainly hosted in the Yinzhubu Formation and the Yanwashan Formation of Ordovician, and genetically related to the Lanhualing granite. The Lanhualing granite belongs to high-K calc-alkaline series with high alkali (Na2O+K2O=4.00%-7.03%), SiO2 (67.87%-74.92%) and MgO (0.62%-1.23%) contents. The granitic rocks show right-dipping chondrite normalized REE patterns with weak δEu anomalies. The granitic rocks are relatively enriched in large ion lithophile elements (LILE) and depleted in high field strength elements (HFSE). The ore-bearing granite was dated at 148.17±0.94 Ma by LA-ICP-MS zircon U-Pb method. The late Yanshanian is the main tungsten mineralization epoch in the South Anhui-north Jiangxi area; and indeed, the Dongyuan, Zhuxi, Yangchuling, Dahutang and other large and super-large tungsten deposits were formed in this period. Geochemical Characteristics of the Lanhualing granite indicate a crustal source but with mantle input under tectonic regime of compression thickening. ©, 2015, Science Press. All right reserved.  相似文献   
48.
Natural Resources Research - Fractal and multifractal models, including the concentration-area (C–A) fractal model, spectrum-area (S–A) multifractal model, and local singularity...  相似文献   
49.
In the western United States, persistent and recurrent flow patterns not only modulate precipitation events but also result in prolonged surface inversion episodes. In this region, the frequency of persistent ridge/trough events ranges between 20 and 40 days, well within the intraseasonal timescale. Based on NCEP reanalysis data starting at 1949, with a focus on the interior West, we observed that episodes of prolonged ridge/trough events appear to occur about a week later every year and resets every 5–7 years—a previously undocumented phenomenon examined herein. Diagnostic analyses indicate that the interplay between regional intraseasonal flow patterns and the North Atlantic Oscillation (NAO) alternates the preferred timeframe for the persistent ridge/trough events to occur. This may result from different phases of the NAO shifting the winter mean ridge and such shifts modulate the occurrence and timing of persistent ridge/trough events. When the timing changes evolve around the quasi-6 years cycle of the NAO, the resultant evolution forms what appears to be a steady phase delay in the ridge/trough events year after year. These results are a further step in disclosing the multiple-scale interaction between intraseasonal and interannual modes and its regional climate/weather impact.  相似文献   
50.
本文将既适用于平面笛卡尔直角坐标系又适用于球面坐标系的基本式同文献[16]中的波向线方程结合,导出波群的波向线散开因子方程。由此方程解出的散开因子是波群组成波的波要素的函数。据此因子连同浅水系数和摩擦系数就可求得波群的波动强度或波高沿波向线的变化。在一定条件下,所导得的方程便分别化为形同于相应坐标系中单频率波的。 所讨论的波群的折射是唯一地由水深变浅所致的。 根据线性势论,得到由波数、波向和频率都彼此稍异的两系正弦波迭加而成的简单波群,海洋中的波群虽较这复杂得多,但两者本质上是相同的。故所提方程可作为计算浅水域中波群的折射系数的模式。  相似文献   
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