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991.
泌阳凹陷核桃园组湖相碳酸盐岩系孢粉相及烃源岩评价 总被引:8,自引:2,他引:6
孢粉相是反映一定沉积物以及成岩作用环境的显微沉积有机质组合。对我国河南泌阳凹陷下第三系核桃园组核三上段至核二段湖相碳酸盐岩系孢粉相进行了详细研究。基于有机质组分的鉴定和统计将碳酸盐岩系划分为五个孢粉相带;并利用孢粉相结合有机质成熟度地化指标,对其生油潜能进行了评价。 相似文献
992.
应用GIS技术进行油气资源评价的探讨 总被引:10,自引:0,他引:10
简要介绍了地理信息系统(GIS)概况,同时讨论了利用GIS进行油气评价的可能性及优越性,并利用此法辽河外围盆地进行凹陷评价,建立了辽河外围盆地地质信息系统,最后应用自组织神经网络对这些凹陷优选排队。 相似文献
993.
A new land surface parameterization scheme (ALSIS), with emphasis on soil moisture prediction, is described and validated with observations from HAPEX-MOBILHY and Cabauw. An important feature of the scheme is the inclusion of vertical heterogeneity of soil hydraulic parameters is modelling unsaturated flow. The simulated soil moisture for HAPEX site using a vertically homogeneous soil has a positive bias in the upper soil layers and a negative bias in the deep soil layers. Taking into account the soil vertical heterogeneity greatly eliminates this discrepancy and results in an excellent agreement between annual cycles of modelled and observed soil moisture profiles. The mean annual soil moisture in the top 1.6 m of soil increased from 394 mm for homogeneous case to 433 mm for the heterogeneous case, consistent with 435 mm observed. The improvement in soil moisture simulation resulted in an improved skill in predicting the mean and the diurnal cycles of surface fluxes for the intensive observational period (28 May–3 July). The simulated monthly averages of surface temperature and fluxes follow observations over the year, except for January when the model overestimates the latent heat flux due to its failure in simulating high rates of dew fall. The deviation of modelled monthly mean surface fluxes from observations are well within the estimated observational errors. The simulated mean daily surface temperature, and surface fluxes are generally consistent with observations, except for some times in the winter period. The modelled diurnal cycles of temperature and fluxes are in agreement with those observed. However, the model overestimates the night-time latent heat flux, especially during January. 相似文献
994.
Xu Liang Eric F. Wood Dennis P. Lettenmaier Dag Lohmann Aaron Boone Sam Chang Fei Chen Yongjiu Dai Carl Desborough Robert E. Dickinson Qingyun Duan Michael Ek Yeugeniy M. Gusev Florence Habets Parviz Irannejad Randy Koster Kenneth E. Mitchell Olga N. Nasonova Joel Noilhan John Schaake Adam Schlosser Yaping Shao Andrey B. Shmakin Diana Verseghy Kirsten Warrach Peter Wetzel Yongkang Xue Zong-Liang Yang Qing-cun Zeng 《Global and Planetary Change》1998,19(1-4)
The energy components of sixteen Soil-Vegetation Atmospheric Transfer (SVAT) schemes were analyzed and intercompared using 10 years of surface meteorological and radiative forcing data from the Red-Arkansas River basin in the Southern Great Plains of the United States. Comparisons of simulated surface energy fluxes among models showed that the net radiation and surface temperature generally had the best agreement among the schemes. On an average (annual and monthly) basis, the estimated latent heat fluxes agreed (to within approximate estimation errors) with the latent heat fluxes derived from a radiosonde-based atmospheric budget method for slightly more than half of the schemes. The sensible heat fluxes had larger differences among the schemes than did the latent heat fluxes, and the model-simulated ground heat fluxes had large variations among the schemes. The spatial patterns of the model-computed net radiation and surface temperature were generally similar among the schemes, and appear reasonable and consistent with observations of related variables, such as surface air temperature. The spatial mean patterns of latent and sensible heat fluxes were less similar than for net radiation, and the spatial patterns of the ground heat flux vary greatly among the 16 schemes. Generally, there is less similarity among the models in the temporal (interannual) variability of surface fluxes and temperature than there is in the mean fields, even for schemes with similar mean fields. 相似文献
995.
Stratagem ^TM EH—4电导率成像系统简介及应用 总被引:18,自引:0,他引:18
EH-4电导率成像系统属于部分可控源与天然场源相结合的一种大地电磁测深系统。由接收与发射两部分组成。根据勘探目的,可选择高频配置或低频配置。通过采集时间域两组相互正交的电磁场信号经过频谱分析及运算,求得不同频率的电阻率,相位及相关度变化曲线。通过分析对比这些曲线,现场判别数据质量,同时对剖面测点的一维视电阻率连续反演结果进行EMAP二维连剖面反演,图示电阻率断面灰度图,可即时对勘测结果进行初步解释 相似文献
996.
Geochemical enrichment and mineralization of indium 总被引:20,自引:0,他引:20
Indium occurs in a very dispersed manner in nature with enrichment of economic interest rarely known. The highly dispersed
nature of indium, among several other elements, has for a long time retarded our understanding of the regularities that control
their mineralization, which in turn has hindered exploitation and application of these elements. Recent studies of ours show
that no significant enrichment of indium can be recognized in various types of Pb-Zn sulphide deposits as well as in deposits
of copper, iron and manganese. Indium concentrations in ores of these deposits are generally below 10 × 10-6. In contrast, however, indium is found to be enriched to a significant extent in cassiterite-sulphide deposits and some tin-rich
Pb-Zn polymetallic deposits. The average content of indium in these deposits can be over 100 × 10-6, and more than 90% of it is concentrated in sphalerite. Generally, these deposits may be considered as large paragenic deposits
for indium and, therefore, there must be some regularities that govern the geochemical enrichment of the so-called “dispersed
element” indium.
This project was financially supported by the National Natural Science Foundation of China (No. 49633110). 相似文献
997.
含煤岩系沉积学和层序地层学研究现状和展望 总被引:35,自引:6,他引:29
在对含煤岩系沉积系研究历史进行回顾的基础上,论述了含煤岩系层序地层学方法以及海平面变化与聚煤作用的关系。注重强调分布广泛的厚煤层实际上是在基准面或海平面的抬升过程中堆积的,煤层底面代表海泛面。 相似文献
998.
Dušan Němec 《Mineralium Deposita》1990,25(4):297-303
In the central Iron Mountains the ore-mineralized deformation zones represent deep reaching faults which possibly reach the upper mantle. During geological history they were used by ascending magmas, fluids, and barren and ore hydrothermal solutions. It can be shown that the metasomatism provoked by acid fluids bears the character of greisenization. The type of the original greisenized rocks here can be determined on the basis of elements that were immobile during greisenization, especially Si, Ti, Sc and REE. After or even during greisenization, the metasomatic rocks were affected by shearing metamorphism corresponding in its PT conditions to the middle zone of the almandine-amphibolite facies. It was possibly in this period that the enigmatic skarn body of Samaov originated. Owing to its similarity to the dyke skarn of Kraskov, its similar origin could be assumed: the deposition of skarn minerals from circulating fluids, which were perhaps released during greisenization. 相似文献
999.
Burak Aydog˘an Berna Ayat Mehmet N. Öztürk Esin Özkan Çevik Yalçın Yüksel 《Ocean Engineering》2010,37(5-6):443-453
Owing to their complex character, modeling flow patterns of narrow straits has always been a challenge, even with the numerical techniques of today. This study was aimed at predicting vertical current profiles of a given point in a narrow strait, the Strait of Istanbul. On account of the speed and simplicity it offers, and of its remarkable success in solving complex problems, the feed forward back propagation (FFBP) artificial neural network (ANN) technique was chosen for this study. The model was built on 7039 hours of concurrent measurements of current profiles, meteorological conditions, and surface elevations. The model predicted 12 outputs of East and North velocity components at different depths in a given location. Various alternative models with different inputs and neuron numbers were evaluated attaining the best model by trial and error. Predictions from proposed ANN model were in accordance with the observations with average root mean square error of 0.16 m/s. The same input parameters were then used to build models that predicted current velocities 1–12 h into the future. Results of these predictions show good overall agreement with observations and that FFBP ANN can be used as a reliable tool for forecasting current profiles in straits. 相似文献
1000.