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121.
HU Ying YIN Jiquan SU Yongdi XIE Yinfu WANG Xiaoxi XIAO Gaojie YU Zhaohua WANG Li 《《地质学报》英文版》2010,84(2):406-414
<正>Exploration and development experience show that there is obvious oil gravity difference between the southern part and northern part of the"M1"reservoir in the Fanny oil field in the slope of the Oriente Basin,Ecuador.The American Petroleum Institute Gravity(API) values of oils in the northern part are higher than the one in the southern part of the Fanny oil field,with the values of 20°and 10.0°-13.0°,respectively.So the primary purpose of this study was to analyze the heavy oil characteristics of biodegradation and the oil-oil correlation according to the biomarker data and theδ~(13)C signature of oil samples from T block.The results of the hydrocarbon gas chromatography fingermark and the inversion attribute characteristics indicated that there are fluid compartments between the"M1"reservoir of Fanny south.Finally,the models of oil-gas accumulation under the control of multiple-activities of complicated fault systems,as well as the origin of heavy oil,are contended.The early stage oils from the western part of the basin were biodegraded heavily in varying degrees in the whole basin,and the later stage oils were derived from the southern part in a large scale and were mature and lighter.Generally,oil mixing is the primary control of net oil properties,such as API gravity in Oriente Basin.We therefore predicted that the API gravity variation of oil pools radically depends on the injection amount of the later stage oil.Because of the shale barrier in the"M1"reservoir of Fanny south,the later stage hydrocarbon could not pass through and contribute to increase the oil API value. 相似文献
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利用我国南方225个测站降水资料和NCEP/NCAR再分析资料,采用线性趋势分析、EOF、合成分析等方法,分析了1961—2010年南方夏季降水异常变化的规律。结果表明:1)南方夏季降水的稳定性从西向东递增。各月中以7月稳定性最差,其次是8月,6月最好;2)南方夏季降水呈东部增多西部减少的分布特征,西部以-5—-20 mm/(10 a)的速率不显著减少,东部大多数区域以5—30 mm/(10 a)的速率不显著增多,其中浙江东部—江苏东南部显著增加;3)南方夏季降水异常主要有全区一致型、南北差异型和东西相反型3种分布模态;西太平洋副热带高压和南支槽是影响南方降水异常的主要系统,两系统的空间配置及其强度变化决定了南方降水异常的不同分布型;4)南方夏季旱涝分布具有相似之处,干旱发生频率高的区域也是洪涝的高频区,但各月分布有差异,夏季及各月的洪涝发生频率高于干旱频率。 相似文献
126.
Forms of phosphorus and silicon in the natural grain size surface sediments of the southern Bohai Sea 总被引:5,自引:0,他引:5
The forms of phosphorus and silicon in the natural grain sizes surface sediments of the southern Bohai Sea were studied. In sediments, the organic matter bound form of phosphorus was the main form of transferable phosphorus and ranged from 0.37μmol/g to 1.57μmol/g, accountingfor 10.7% of the total phosphorus, others were the carbonate bound form, iron-manganeso oxide bound form and ion-exchange able form; the transferable form of phosphorus accounted for 19.2% of the total phosphorus. Silicon‘ s carbonate bound form was predominant over others among its transferable forms, and content ranged from 1.55μmol/g to 8.94μmol/g, accounting for 0.05% of the total silicon; the total amount of transferable silicon forms accounted for only 0.12% of the total silicon. Therefore, 19.2% of the total phosphorus and 0.12 % of the total silicon contained in the surface sediments of the southern Bohai Sea could participate in the biogeochemical cycling. 相似文献
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提出了一种基于小波包变换和误差扩散的打印扫描图像水印算法。首先对图像进行三层小波包分解,并将其作为水印嵌入到分解后的高频分量的低频子带,然后进行小波包重构得到嵌入水印的图像,再运用改进的噪声平衡误差扩散算法加网得到含水印的半色调图像。实验表明,该算法对于打印扫描过程的无意攻击具有良好的鲁棒性。 相似文献
129.
A review on the mechanism and affecting factors of nitrous oxide emission in constructed wetlands 总被引:2,自引:1,他引:1
Constructed wetlands (CWs) are considered important sources of nitrous oxide (N2O). Various reports in the literature indicate that CWs have high N2O emission rates. The release of N2O from CWs treating wastewater emissions range from ?16.7 to 188 mg N2O m?2day?1. N2O in CWs is produced mainly by nitrification, denitrification, nitrifier denitrification, and nitrate-ammonification. Denitrification is considered the major source of N2O under most conditions. In recent years, two main methods of sampling N2O gas in CWs have been employed, including the headspace equilibration technique and the closed static chambers technique. N2O emission may be affected by various operating parameters and environmental conditions. One of the main environmental factors affecting the removal of nitrogen in CWs is dissolved oxygen, which affects nitrification and denitrification processes, thus greatly influencing N2O emission. CW gas dynamics is affected mainly by season and weather conditions, especially temperature and moisture. Aquatic plants, flow regime, oxidation–reduction potential, nitrate concentration, C/N ratio and other factors can affect N2O emission in CWs. 相似文献
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利用长白山森林生态系统定位研究站观测资料,及2003年8月和9月涡旋相关资料,分析和比较了该地区近地层包括风速、风向、大气稳定度在内的平均场特征,以及湍流强度、无量纲化风脉动方差相似性和地表通量变化特征。结果表明:(1)8月和9月稳定度都基本集中在0附近;(2)风速2 m·s-1的环境中,湍流发展最为旺盛,随着风速的增大湍流强度先迅速减小,当风速增大到3 m·s-1后,湍流强度偏离0值变大了一些,再继续增大到一定风速大小以后,湍流强度基本不随风速变化;(3)无量纲化三维风脉动方差符合Monin-Obukhov相似理论的"1/3"定律,其最佳通用相似函数在稳定和不稳定条件下都可以拟合得到;(4)地表通量均表现出明显的日变化特征,8月以潜热为主,感热较小;9月仍以潜热为主,但是相比8月明显偏小,感热变化不大。 相似文献