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871.
基于弹性波阻抗的拉梅参数反演与应用 总被引:3,自引:0,他引:3
(Connolly的弹性阻抗(EI)公式是纵、横波速度、密度和入射角的函数,应用该公式的常规反演方法只能直接得到纵、横波速度和密度的信息,而且不同角度的弹性阻抗在数值上差别很大,不在同一尺度上,无法进行对比。本文针对常规反演方法的缺点,提出了基于Gray的Zoeppritz近似方程的新的弹性阻抗公式,并对这个公式进行了标准化以实现不同角度的弹性阻抗在数值上的统一,最后用标准化后的公式进行了反演,利用拉梅参数与弹性阻抗问的线性关系可从反演得到的弹性阻抗数据体中直接提取得到拉梅参数。应用实例表明用这种方法提取得到的弹性参数更加稳定、准确,而且能很好地反映储层信息。这种新的方法是对以Connolly公式为基础的传统方法的改进。 相似文献
872.
Acoustic Emission Experiments of Rock Failure Under Load Simulating the Hypocenter Condition 总被引:3,自引:0,他引:3
Hui-hui Zhang Xiang-chu Yin Nai-gang Liang Huai-zhong Yu Shi-yu Li Y. C. Wang C. Yin Victor Kukshenko Nikita Tomiline Surguei Elizarov 《Pure and Applied Geophysics》2006,163(11-12):2389-2406
A series of acoustic emission (AE) experiments of rock failure have been conducted under cyclic load in tri-axial stress tests. To simulate the hypocenter condition the specimens are loaded by the combined action of a constant stress, intended to simulate the tectonic loading, and a small sinusoidal disturbance stress, analogous to the Earth tide induced by the Sun and the Moon. Each acoustic emission signal can indicate the occurrence time, location and relative magnitude of the damage (micro-crack) in the specimen. The experimental results verified some precursors such as LURR (Load/Unload Response Ratio) and AER (Accelerating Energy Release) before macro-fracture of the samples. A new parameter, the correlation between the AE and the load, has been proposed to describe the loading history. On the eve of some strong earthquakes the correlation between the Benioff strain and the Coulomb failure stress (CFS) decreases, similar to the variation of LURR prior to strong earthquakes. 相似文献
873.
874.
The Connolly (1999) elastic impedance (EI) equation is a function of P-wave velocity, S-wave velocity, density, and incidence
angle. Conventional inversion methods based on this equation can only extract P-velocity, S-velocity, and density data directly
and the elastic impedance at different incidence angles are not at the same scale, which makes comparison difficult. We propose
a new elastic impedance equation based on the Gray et al. (1999) Zoeppritz approximation using Lamé parameters to address
the conventional inversion method’s deficiencies. This equation has been normalized to unify the elastic impedance dimensions
at different angles and used for inversion. Lamé parameters can be extracted directly from the elastic impedance data obtained
from inversion using the linear relation between Lamé parameters and elastic impedance. The application example shows that
the elastic parameters extracted using this new method are more stable and correct and can recover the reservoir information
very well. The new method is an improvement on the conventional method based on Connolly’s equation.
Wang Baoli graduated with a Bachelor’s degree in Prospecting Information and Engineering from the China University of Petroleum (East
China) in 2004 and earned her Master’s degree from the department of Geophysical Prospecting and Information Technology in
the China University of Petroleum ((East China) in 2006. She now studies for her PhD at the China University of Petroleum
(East China). Her research interest is elastic impedance inversion. 相似文献
875.
876.
煤矸石的淋溶、浸泡对水环境的污染研究——以兖济滕矿区塌陷区充填的煤矸石为例 总被引:5,自引:1,他引:5
通过对兖济滕矿区长期充填煤矸石的塌陷区内地表水、浅层地下水中有害微量元素的分析,研究了淋溶、浸泡两种长期行为对煤矸石中有害微量元素析出的作用机理,认为煤矸石被用来充填塌陷区是可行的,但潜在的危害还是值得进一步的研究和引起重视。 相似文献
877.
针对所承担工程任务的要求,采用目前较为成熟的数值计算方法,将根据地震危险性分析计算得到的库车河铜场水库的地震动参数(3 种概率水平)转换成模拟的地震动加速度时程。因为计算中直接采用了新疆地区乌恰强余震频谱,合成的基岩地震动加速度时程很好地反映了该地区的工程特性 相似文献
878.
Xiwei Yin 《Meteorology and Atmospheric Physics》1998,68(1-2):99-113
Summary A general lack of information on atmospheric optical properties (e.g., the transmission coefficient) is a major obstacle to the use of the Lambert-Beer Laws in numerical modeling. This paper reports on an effort to extract those properties from solar irradiance records and capture their variations in relation to commonly available climatic information. The end product of the effort is a Lambert-Beer Laws-based model that is complete with functions projecting atmospheric coefficients and that differentiates direct, sky-diffuse and terrestrially-reflected solar irradiance. The model is driven by calendar day, four location factors (latitude, elevation, slope azimuth, slope inclination) and three climatic variables (bright-sunshine duration, precipitation, temperature). It effectively reproduces monthly solar irradiance data from around the world. 相似文献
879.
A comparison of drainage networks derived from digital elevation models at two scales 总被引:2,自引:0,他引:2
Automated generation of drainage networks has become increasingly popular with powerful analytical functions in geographic information systems (GIS) and with the increased availability of digital elevation models (DEMs). This paper compares drainage networks derived from DEMs at two scales, 1:250 000 (250K) and 1:24 000 (24K), using various drainage parameters common in hydrology and geomorphology. The comparison of parameters derived from the 250K DEMs with those from the 24K DEMs in 20 basins ranging from 150 to 1000 km2 in West Virginia shows that the goodness-of-fit between parameter estimates based on the DEMs varies. Results clearly show that superior estimations are produced from the 24K DEMs. Better estimates can be obtained from the 250K DEMs for stream length and frequency parameters than for gradient parameters. However, the estimation of the mean gradient parameters based on the 250K DEMs seems to improve with increasing terrain complexity. Finally, basin size does not strongly affect the accuracy of parameter estimates based on the 250K DEMs. 相似文献
880.