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991.
992.
陆丰凹陷T5反射层整体上为3个正向和2个负向同相轴组成的(较)强反射波组,其中部为正向轴,即本次研究追踪的T5反射轴连续、分布广、最稳定,在深洼区为下超终止面,向岸或古地貌高地为上超面,是最好的区域对比和地震追踪标志层。T5反射层整体对应3个岩性层段,其中部岩性段为灰岩或与之可对比的灰岩与砂泥岩的互层,陆丰凹陷北西部则均为砂泥岩,并对应T5反射轴,年龄185 Ma,为三级层序TB21最大洪泛期前后的沉积,是南海运动以来海水整体变深背景下,陆丰凹陷首次由滨海过渡到浅海陆架的一次明显海侵期沉积。中部岩性段之上常为一套砂岩层及再向上的泥岩发育段,为TB21下降体系域和另一期海侵沉积;中部岩性段之下邻接的砂泥岩互层层段为TB21内的一个四级层序。T5反射层对应灰岩与其上下不同级别层序界面附近储盖组合有利;层序的旋回变化及继承性发育的地貌高地是该层段油气有利勘探区带平面展布的主控因素。 相似文献
993.
随着测绘技术在经济、文化、农业、国防等方面的应用,对测绘技术水平要求越来越高.本文探讨了通过高分辨率卫星影像快速更新地形图的优势,分析现阶段应用过程中存在的问题,并提出了解决思路. 相似文献
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检验分析了湖北省MAPS数值降水预报产品对长江中上游嘉陵江、三峡区间东段、西段和清江流域面雨量的预报精度,并对造成空漏报的天气系统进行了分类统计分析.得到的若干结论有助于该类产品在业务预报中的应用. 相似文献
997.
冰芯与寒区环境开放研究实验室的回顾与展望 总被引:3,自引:1,他引:2
History and current situations of ice core research in China are reviewed following the establishment of the Laboratory of Ice Core and Cold Regions Environment, CAS. At present, three research foci are mainly carried out in the laboratory, namely: (1) Interaction between glacier and atmosphere; (2) Ice core records; (3) The physics of snow and ice. Within the passing several years. over forty projects have been finished or are being carried out. and about 300 papers were published in various international or domestic scientific journals and 9 monographs were published too. The research results have been awarded two first-class prizes by the Chinese Academy of Sciences, one third-class national prize. and one fourth-class national prize. Intensive cooperation with authoritative research institutions has contributed much to the laboratory. which will be continuously emphasized in the future. 相似文献
998.
中国南极冰川学研究10 a回顾与展望 总被引:13,自引:7,他引:6
The study of Antarctic glaciology in China is reviewed with the emphasis on the past decade. Much progress has been achieved in the physical characteristics of the Antarctic ice sheet and caps and in the study of climatic and environmental records in Antarctic snow and ice. Through observations of snow profiles of numerous snow-pits and shallow cores in the Wilkes Land and Lambert Glacier basin and along the route of the 1990 International Trans-Antarctica Science Expedition (ITASE), the regional features of snow deposition and densification in Antarctica were revealed. The Nelson Island ice cap in South Shetland Islands was investigated in detail that greatly enriched the knowledge of glaciers under a sub-Antarctic maritime climate. From the analyses of shallow ice cores and surface snow samples, in particular those taken along the ITASE route, the systematic data of stable isotopes, soluble impurities and heavy metal Pb in present precipitation in Antarctica has been obtained. Some suggestions are proposed through discussing the present hot points in the above fields. 相似文献
999.
The study on the depositional styles of major ions and the climatic effect of nssSO_4~(2-)in Princess Elizabeth Land, Antarctica 下载免费PDF全文
Snow samples collected from a 50 m firn core and two snow pits along the route of the 1996/1997 Chinese First Antarctic Inland Traverse Expedition in Princess Elizabeth Land, East Antarctica, have been analyzed for chemical composition and oxygen isotope ratio. Analyzing the relationship between the concentration and flux of major ions and accumulation rate can draw the following conclusions. 1) The concentrations of major ions in the atmosphere in the study region is big enough so that the concentrations of the ions do not vary with snow accumulation rate, that is to say, the concentrations of major chemical species are independent of snow accumulation rate. 2) The results of analyzing the depositional styles of major chemical species suggest that wet deposition dominates the major ions flux. In addition, there is no apparent correlation between nssSO 2- 4 fluctuations and isotope profile. This would indicate the short-term climatic effect of volcanism is not evident in the region. 相似文献
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