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991.
By use of GMS-4 infrared brightness temperature and visible albedo data from January toFebruary in 1995,the method for extracting of sea ice parameters is developed.The digital remotesensing picture is obtained on Liaodong Bay.Based on the difference in physical properties betweenice and water,a criterion distinguishing ice from water is set up.Ice thickness has been calculatedaccording to the relationship between ice thickness and brightness as well as albedo.Iceconcentration is retrieved due to the difference on albedo between ice and water.The resultsindicate that the accuracy of ice-water distinguishing is 84.8%,the errors of ice thickness and iceconcentration are 3.8 cm and 22%,respectively. 相似文献
992.
<正> 一、深化我院科技体制改革的必要性和紧迫性 中国地质科学院是我国地质行业专业齐全、技术力量雄厚、规模最大的综合性地质科学研究机构,创立于1956年,现隶属国土资源部。几十年来,中国地质科学院的研究机构几经调整分合,所属研究单位最多时曾达到23个,人员近7000人。建院44年来,地科院 相似文献
993.
山东省林业科学研究所 《湿地科学与管理》2000,(1):45-46
<正> 山东省林业科学研究所是以应用基础研究、应用研究和开发性研究为主的林业综合性科研机构。建所四十多年,在广大科研人员共同努力下,取得了100余项省部级以上的科研成果,为振兴山东林业,促进经济发展发挥了巨大作用。特别是改革开放以来,随着社会主义市场经济的建立和发展,科技体制改革的不断深入,全所同志解放思想,更新观念,认清形势,明确了科技发展思路。经过几年努力和探索,走出了一条适合我所实际的科技产业化道路,创造了较大的社会、经济效益。自1997年以来,全所科技企业和实体产 相似文献
994.
A deep-sea Manned Submarine Vehicle (MSV) is usually required to move at a low forward speed and a low rotational speed when it executes investigation tasks. In this condition, the motion is in large drift angles, and the maneuverability hydrodynamic forces cannot be expressed properly in the conventional mathematical model of submersible motion. In this paper, firstly, a general equation of MSV with six-freedom motion is presented, and the numerical simulation of descent/ascent motion and helix motion is c... 相似文献
995.
According to the mechanism of sediment suspension under waves,namely,the main reason of sediment suspension changes from the turbulent mixing in the bottom boundary layer to the periodic motion of the water particle near the free water surface,a three-hyer model d sediment concentration distribution due to waves is presented along the whole water depth based on the concept of the finite mixing |ength.The determination of the parameters in the model is discussed and an empirical formula is suggested.Comparisons between the calculated results and the measurements indicate that the resuits of the model agree well with the data from both the large and small scale flume experiments. 相似文献
996.
REN Shoumai LIU Yongjiang GE Xiaohong . Strategic Research Center of Oil & Gas Resources Ministry of L & Resources Beijing China . College of Earth Sciences Jilin University Changchun China 《东北亚地学研究》2009,(3):145-155
The latest sharp uplift of the Tibetan Plateau and adjacent mountains occurred at the end of the early Pleistocene. The uplift of the Plateau resulted from Late Mesozoic-Cenozoic compressional structure due to the subduction of the Indian Plate beneath the Asian continent. This event definitively effected the formation of basin-mountain relief, Cenozoic basin deformation, large scale aridity and desertification of western China. The Australasian meteorites impact event happened ca. 0.8 Ma ago, located in the triangle area of the Indian Ocean ridge (20°S/67°E). The impact may have resulted in an acceleration of speeding of the Indian Ocean ridge pushing the Indian Plate to subduct rapidly northward. Thus, the impact event can give reasonable explanation for the dynamic background of the latest rapid uplift of the Tibetan Plateau and the continental deformation of western China and even of the Middle Asia. 相似文献
997.
WANG Qing FAN Jianhua FANG Ming ZHANG Li .College of Construction Engineering Jilin University Changchun China .China Northeast Municipal Engineering Design Research Institute Changchun China 《东北亚地学研究》2009,12(1):13-16
In China, seasonal frozen soil is widely distributed. The freezing damage of subgrade soil in Jilin Province has been one of major engineering geological problems troubling the safety of road, in which some common damage phenomena, such as frost heave, subsidence deformation and frost boiling, are all caused by water translocation. Aiming at the phenomenon, the changes of moisture content of seasonal frozen soil in Changchun City are mainly studied by long-term field observation and indoor testing of physical properties under different conditions, and then the variation characteristics of moisture content in soil under different compactness and temperature conditions are realized. The results show that the increasing section of moisture content and negative temperature section all lie in O. 0 - 1.0 m of subgrade. Both lowest air and earth temperature occur in January to February, and the most negative temperature ranges from -7℃ to -10℃. 相似文献
998.
The size-fractionated phytoplankton biomass, and the spatial and temporal variations in abundance of Synechococcus (SYN) and picoeukaryotes (PEUK) were measured in the Taiwan Strait during three cruises (August 1997, February-March 1998, and August 1998). The results show that picophytoplankton and nanophytoplankton dominate the phytoplankton biomass, in average of 38% and 40%, respectively. SYN and PEUK varied over time in abundance and carbon biomass, greater in summer than in winter, in range of (7.70–20... 相似文献
999.
Effects of salinity, light and temperature on growth rates of two species of Gracilaria (Rhodophyta)
Effects of temperature, salinity and light intensity on growth rates of Gracilaria lichenoides and G tenuistipitata var. liui Zhang et Xia were tested. Eight to ten levels of each factor were first tested separately. The best growth rate was obtained under the conditions of 32~C, 30 and 240 μmol/(m2·s) for G. lichenoides, and 24℃, 20 and 200 μmol/(m2.s) for G. tenuistipitata, respectively. Then a uniform design was used to evaluate the optimal combinations of the three factors. The best conditions for the highest daily specific growth rates (% increase in wet weight) are determined to be 31.30℃, 32.10, and 287.23 μmol/(m2·s) for G. lichenoides (16.26%/d), and 25.38℃, 21.10, and 229.07 μmol/(m2·s) for G. tenuistipitata (14.83%/d), respectively. 相似文献
1000.
根据露头剖面、钻测井资料,分析和总结了川中广安地区上三叠统须家河组(T3x,原称香溪群)的岩相组合、沉积特征及有利储层评价。研究区内须家河组可识别出11种岩相类型、7种岩相组合。川中广安地区在须家河组沉积时期,主要发育了湖泊沉积体系和3个三角洲沉积体系,三角洲砂体以三角洲平原辫状河道与三角洲前缘水下分支河道微相的正韵律砂体叠置发育为特征,三角洲体系中的主干河道叠置带明显控制了有利储层的平面分布,三角洲平原-前缘的过渡区为最有利储层的发育区。 相似文献