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391.
松林坡金矿2002年新发现。矿体主要受浅成 超浅成侵入体及其内部和附近的断裂 裂隙系控制。多种控矿条件的复合、匹配对金矿成矿起制约作用:岩脉、岩体受断裂及两组以上断裂交汇控制,矿质来源、成矿流体来源多样化,矿(化)体明显具多种蚀变作用叠加特征。 相似文献
392.
宣达盐盆富钾富矿卤水产于四川盆地东北部黄金口背斜群南段付家山构造近高点,以深层卤水形式赋存于3260m左右的下三叠统嘉陵江组五段和中统雷口坡组一段(T1j5-T2L1)盐系的碳酸盐岩储层中。卤水与海水蒸发系列相比,K+含量异常高,达25 96g L,超过海水钾盐沉积阶段,也超过综合利用和单独开采品位,为国内外罕见的液态钾矿资源。且富含I-,B3+,Li+,Rb+,Sr2+等多种有用组分,品质优异,构成优质化工原料水,为一种综合性富钾富矿液态矿藏,经济价值极高。卤水为沉积变质水和固态钾盐溶滤水的复合成因。开发利用将可为农业提供优质钾肥,缓解我国钾盐资源不足,并可提供多种短缺的化工产品,对固态钾盐找矿具有重要现实意义。 相似文献
393.
某地基不均匀沉降的三维分析 总被引:3,自引:2,他引:3
某地基处理原拟采用CFG复合地基。但由于地层情况复杂 ,施工难度大 ,决定采用CFG桩和人工挖孔桩进行地基处理 ,但是这种处理方案可能会引发地基不均匀沉降从而对上部结构产生不良影响 ,因此合理的的选取人工挖孔桩桩间距非常重要。通过对四种桩间距情形下地基的三维沉降分析 ,选取了合理的人工挖孔桩桩间距 ,解决了这一工程难题. 相似文献
394.
消除影响压实趋势线地质因素的方法--以莺歌海盆地为例 总被引:8,自引:0,他引:8
莺歌海盆地第四系和上第三系地层内除异常压力和压实作用外,影响声波时差的因素主要有岩性变化、成岩胶结作用、地层含天然气及裂缝的存在。这些因素在地层中往往同时存在,难以区分和辨识。借用地震处理过程中多道曲线叠合以增强信噪比的思路,通过局部区块上数口井声波时差压实曲线的叠合处理,反映地层孔隙特征的信息量得到增强,是可避开或消除影响声波速度地质因素的一种有效方法。进一步将这种方法移植到地震速度谱资料的处理中,获得的压力预测结果得到钻井实测压力的证实。 相似文献
395.
DIFFERENTIATION DIRECTION OF TELLURIC CURRENTS IN THE SOUTHERN SECTION OF THE TANLU FAULT ZONE 下载免费PDF全文
The Tancheng-Lujiang Fault is an important tectonic boundary in eastern China. The southern part of the Tancheng-Lujiang Fault is located south of Baohai Bay, which is an area with a dense population and frequent economic activities. It is worth conducting an in-depth study on the southern section of the fault, especially in the aspect of geophysical exploration and seismicity analysis. Electrical structure detection is an important way to interpret the structural activity of the fault. It can also analyze and explore the influence of the fault on the physical properties of both sides of the fault based on the geoelectrical observation data. In the study area, there are densely distributed stations of geoelectrical observation, including 27 fixed stations distributed along the fault zone from the southern Baohai Bay to Nanjing, Jinagsu Province. The continuous observations and recording of these stations provide a favorable condition for studying the tectonic activity of Tancheng-Lujiang Fault.
In the long-term observation of geoelectric observation network, the geoelectric field measurements of long- and short-spacing measuring tracks in the same direction at the same station vary significantly because of the effect of long-term stability of the observation system and the environment near the electrodes. Also, the data curve changes complicatedly and seems to be in a mess. However, there are three basic facts of observation existing in the geoelectric field change: 1)The variation amplitude of the geoelectric field changes observed on the long- and short-spacing measuring tracks in the same direction at the same station(including tidal response changes and the rapid change events such as short periods or pulses)is the same or very close; 2)The Ex and Ey components at the same station always show the same variation in the same time period, or the opposite, which is related to the anisotropy of the medium under the station; 3)The rapid changes of the minute values of the geoelectric field observed at different stations are synchronous in a wide spatial area. In this study, in order to take full advantage of these basic facts, we only use the amplitude variation of geoelectric field with time.
Based on the data of 27 geoelectric field observation stations in the study area, we used the current density vector and streamline to characterize telluric current with its divergence and vorticity calculated in the southern Tancheng-Lujiang Fault in this paper. The results show that: 1)the telluric current shows the phenomenon of opposite directional differentiation in the southern part of the fault zone, the direction of the current vector is NE on the east side, while the direction is NW to SW on the west side; (2)The divergence and vorticity of telluric current also show the differentiation phenomenon along the fault, the positive/negative maximum of vorticity and divergence mainly occurs near the fault zone and the direction of alternating positive and negative gradient(or negative gradient)of vorticity or divergence is consistent with the strike of the fault zone. By analyzing the current superposition simulation results and comparing them with previous studies, an interpretation model of the above phenomenon is established in this paper. The results agree with previous studies on the electrical structure of this region. Besides, the results that telluric current differentiates along the fault zone may improve our understanding of the process of deep electrical and material migration. 相似文献
396.
Nonlinear lateral interaction in pile dynamics 总被引:4,自引:0,他引:4
A model for pile lateral response to transient dynamic loading and to harmonic loading is presented allowing for nonlinear soil behaviour, discontinuity conditions at the pile-soil interface and energy dissipation through different types of damping. The approach is used to establish equivalent linear stiffness and damping parameters of single piles as well as dynamic interaction factors for approximate nonlinear analysis of pile groups. The applicability of these parameters to the pile-group analysis was examined, and a reasonable agreement with the direct analysis was found. The superposition technique may be used to analyze the response of small pile groups. Also, the dynamic stiffness of pile groups is greatly affected by both the nonlinear behavior of the soil and the slippage and gapping between the pile and soil. For a basic range of soil and pile parameters, equivalent linear stiffness and damping parameters of single piles and interaction factors for approximate nonlinear analysis are provided. 相似文献
397.
为了适应面广量大且需求仍在不断增长的1:5万专题调查制图的需要,我们采用数字插值放大、优化波段组合的光机复合处理技术,探索了1:5万高质量TM影像图的制作技术。本文介绍了制作1:5万高质量TM影像图的基本工艺方案及技术关键:(1)对TM图像磁带数据进行实数倍(2.28倍)双向线性插值放大,(2)在C-4500扫描仪上用50μm光点扫描获得比例尺为1:25万的潜影图像,(3)把潜影图像经显影、定影处理,再光学放大5倍,获得1:5万TM影像图。从我们结合有关任务先后在河北省南皮县、黑龙江省穆稜县和山东省莱洲湾等地区进行的试验研究看,均取得了良好效果。 相似文献
398.
399.
400.
求解结构动力响应的小波分解法 总被引:1,自引:1,他引:0
本文用时程分析、振型迭加和小波变换3种方法,对一个10层建筑结构的地震动力响应进行了计算和比较,三者的结果完全一致,从而说明了线性时不变系统结构动力响应的唯一性定律是正确的。由于时程分析法可以用于非线性系统,而振型分解法只能用于线性系统,小波变换不但可以用于非线性,更可以用来进行多尺度分析的能谱计算,它能使抗震分析从传统的滞回耗能模型,提高到以结构损伤和延性评价的体系上来。 相似文献