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991.
随着新型城镇化建设成为了国家战略,各地政府掀起了智慧城市建设热潮。在智慧城市建设中,公共信息平台建设是不可或缺的重要基础环节。随着平台的深入运行,逐步积累了大量的城市数据。但是,数据资源中蕴含的知识远未得到充分挖掘和应用,致使数据爆炸但知识匮乏。因此,基于数据时空和专题属性,建立科学的城市数据体系是城市管理的迫切需求;同时,基于数据体系,揭示各类数据随时空变化规律,展现城市脉动发展情况是城市决策重要的依据,也是观察和诊治"城市病"的重要技术手段。我们以中新天津生态城所建成的大数据汇聚公共平台为依托,基于数据挖掘技术手段,针对环境、能源、交通脉动进行研究并取得初步成果,科学地揭示了"城市脉动"变化规律,使平台数据发挥最大价值。脉动分析结果以可视化手段表现,反映城市各项指标脉动变化特征。 相似文献
992.
993.
地理信息服务可以应用到客户资源分析、运营成本分布管理、人力资源管理、信贷风险管控、实物资产管理等多个领域。目前,中国农业银行公共地理信息服务建设还处于空白阶段。为提高全行网点管理水平,有效地推动网点转型工作,迫切需要公共地理信息服务平台的支持。本文从中国农业应用金融GIS云平台建设的实际出发、阐述了平台的设计和实现。 相似文献
994.
995.
2020年秋季(9—11月)大气环流特征表现为,北半球极涡呈单极型分布,中高纬环流呈4波型。9—11月,欧亚大陆中高纬环流经向度不断加大,冷空气势力增强。西太平洋副热带高压较历史平均偏强,热带气旋活动频繁。我国近海出现了19次8级以上大风过程,其中冷空气大风过程6次,台风大风过程4次,入海气旋大风过程1次,冷空气与热带气旋共同影响的大风过程7次,冷空气和温带气旋共同影响的大风过程1次。西北太平洋和南海共生成13个热带气旋,其中10月共有7个热带气旋生成,追平10月热带气旋生成数的历史最高纪录;全球其他海域共生成热带气旋26个。我国近海未出现2 m以上大浪过程的天数仅有12 d,约占秋季总日数的13%。秋季,我国近海海域呈明显降温过程,北部海域的降温幅度明显大于南部海域,受连续北上影响我国北部海域的热带气旋活动影响,9月黄海东部及东海东部的海面温度较气候态明显偏低。 相似文献
996.
V. V. Baranov 《Stratigraphy and Geological Correlation》2007,15(5):470-484
Data on Middle and Upper Devonian deposits studied in southeastern flank of the Siberian platform are considered. A scheme of stratigraphic zoning in the study region is presented. Nineteen sedimentological and biotic events, which are recorded in the studied sections, are of the regional, interregional and global ranks. Their connection with eustatic sea-level fluctuations is established. Sections of the formation and regional horizon stratotypes and parastratotypes are described. The revision of species Mucrospirifer novosibiricus (Toll) is carried out. 相似文献
997.
The sea level series of Stockholm in the Baltic Sea, commencing already in 1774, is analysed in various ways together with contemporary climate data, in order to investigate long-term sea level changes and their relations to climate changes.First, a study of the eustatic rise of sea level, based on annual mean sea levels, is peformed, and compared with other sea level and climate studies. It is concluded that the general climatic rise of sea level has increased significantly (99.9%) from about 0.0 mm/year during the end of the Little Ice Age, to about 1.0 mm/year during the past century, characterized by melting of glaciers. Such sea level changes due to northern hemisphere climate variations since 800 A.D. have (hitherto) probably always kept within −1.5 and +1.5 mm/year, with an average fairly close to zero.Second, an investigation of the sea level variability, also based on annual mean sea levels, is performed together with temperature and wind variabilities. It is found that the interannual sea level variability of the Baltic Sea has decreased significantly (98%) from the end of the 1700s to the beginning of the 1900s; after that it has increased significantly (95%) again. Precisely the same is found to apply to winter climate or, more specifically, to the interannual winter temperature variability and the interannual winter wind variability. The common origin of all these long-term changes turn out to be two consecutive winter wind processes over the North and Baltic Seas, especially the Baltic entrance. From the end of the 1700s to the beginning of the 1900s, there has been a rapidly decreasing number of dominating winter winds from northeast, and after that there has been an increasing number of dominating winter winds from southwest. This may indicate corresponding long-term changes in the North Atlantic Oscillation.Third, using monthly mean sea levels together with corresponding wind data, seasonal variations are investigated. The seasonal sea level variation in the Baltic Sea has increased significantly (99%) since the early 1800s, together with a shift of the maximum from late summer to early winter. It is found that the main origin is a secular change of the winter wind conditions over the Baltic entrance, with increasing southwesterly winds in early winter. This might also be related to a long-term change in the North Atlantic Oscillation. 相似文献
998.
珠江三角洲海平面上升对堤围防御能力的影响 总被引:13,自引:1,他引:12
珠江三角洲2030 年海平面上升幅度约为30 cm 。按此,由水力学模型计算了24 个站最高洪潮水位的升幅, 以5 cm 和25 cm 等值线划分出影响很小区、影响较大区、影响最大区。由水文学方程计算了17 个站4 种重现期的最高洪潮水位升幅, 得知现有堤围的防御标准在影响较大区将降低半个等级, 在影响最大区将降低一个半等级。受影响的堤围长度为2 608 km , 维护工作量为1 752×104m 3, 需投资21 亿元 相似文献
999.
Jon E. Mound Jerry X. Mitrovica David A. D. Evans & Joseph L. Kirschvink 《Geophysical Journal International》1999,136(3):F5-F10
The possibility of inertial interchange true polar wander (IITPW) events, in which the rotation pole moves 90° with respect to the solid Earth in a matter of ∼10 Myr, has been discussed in the geophysical literature for more than three decades. Recent evidence for an IITPW event in Early Cambrian time has renewed interest in the issue; however, the veracity of supporting palaeomagnetic evidence remains a matter of significant debate. We propose that sea-level variations driven by polar wander provide an important independent test for the occurrence of IITPW events. Our numerical simulations of the response of a viscoelastic planet to an IITPW-induced forcing predict sea-level changes of up to 200 m, depending on the details of the earth model, the location of the site relative to the rotation path and the elapsed time for the reorientation of the pole. A preliminary comparison of our predictions to Early–Middle Cambrian sea-level records for Australia, Laurentia and Baltica shows qualitative agreement. This comparison suggests that a definitive test for the Cambrian IITPW hypothesis is possible given a sufficiently accurate, and globally distributed, database of sea-level histories. 相似文献
1000.
Abdullah M. S. Al-Amri 《Geophysical Journal International》1999,136(2):421-430