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941.
942.
使用红外云图、多普勒雷达回波的强度场、速度场及VAD产品,对2002年7月24日夜间至25日凌晨的中天山及其北部地区的强降水天气过程进行了分析、诊断,得出对降水过程不同时段临近预报有指导意义的结论和指标。 相似文献
943.
本文主要介绍了Trimble 5700测地型卫星定位仪的主要性能、在油田井位勘定中的应用及其软件数据处理统计分析。 相似文献
944.
About three quarters of superlarge porphyry copper deposits throughout the world occur along the eastern Pacific basin rim, most of which were formed during the Mesozoic-Cenozoic. Porphyry copper deposits often occur in the upper parts of a subduction zone and in a within-plate orogenic belt. Some porphyry copper deposits are inconsistent with plate subduction with respect to their formation time, and most of them in the world are associated with tensional environment. Metallogenic porphyries originated from the mantle, and the involvement of the lower-crust or oceanic crust materials have played an important role. Based on the geochemical characteristics and tectonic settings of the ore-bearing porphyries in the Gandise and Yulong metallogenic zones, it is proposed that delamination may be the important mechanism of formation of porphyry copper deposits. 相似文献
945.
新沂台地电阻率整点值的远大震前驱波变化 总被引:3,自引:1,他引:3
介绍江苏新沂台地电阻率整点值观测资料中的一种新变化——远大震前驱波,并简单分析了产生这种变化的机理。这一变化对预测远大震具有前兆意义,值得进一步深入研究。 相似文献
946.
Multichannel analysis of surface wave method with the autojuggie 总被引:2,自引:0,他引:2
Gang Tian Don W. Steeples Jianghai Xia Richard D. Miller Kyle T. Spikes Matthew D. Ralston 《Soil Dynamics and Earthquake Engineering》2003,23(3):61-65
The shear (S)-wave velocity of near-surface materials and its effect on seismic-wave propagation are of fundamental interest in many engineering, environmental, and groundwater studies. The multichannel analysis of surface wave (MASW) method provides a robust, efficient, and accurate tool to observe near-surface S-wave velocity. A recently developed device used to place large numbers of closely spaced geophones simultaneously and automatically (the ‘autojuggie’) is shown here to be applicable to the collection of MASW data. In order to demonstrate the use of the autojuggie in the MASW method, we compared high-frequency surface-wave data acquired from conventionally planted geophones (control line) to data collected in parallel with the automatically planted geophones attached to steel bars (test line). The results demonstrate that the autojuggie can be applied in the MASW method. Implementation of the autojuggie in very shallow MASW surveys could drastically reduce the time required and costs incurred in such surveys. 相似文献
947.
Yu Huaizhong Yin Xiangchu Liang Naigang Xia Mengfen Li Min Xu Zhaoyong Peng Keyin Victor Kukshenko Wu Zhishen Qi Li Surguei Elizarov 《中国地震研究》2003,17(3):227-235
Implementing acoustic emission experiments with large rock samples, LURR (Load/Unload Response Ratio) theory was studied. The loading conditions in the experiments were designed to simulate the complicated loading process of underground rocks. The damages emerging inside the rock samples were recorded by the acoustic emission technique during the loading process. The experimental results were consistent with prediction by LURR theory. Integrating the changing processes of LURR value Y and the location process of acoustic emission events showed agreement between the variation of LURR value Y and the damage evolution inside the rocks. Furthermore, the high value of Y emerged before the complete breakdown of materials. Therefore, the damage evolution of rock specimen can be quantitatively analyzed with LURR theory, thus the failure of the rock materials and the earthquake occurrence may be predicted. The experimental results gave a further verification of LURR theory. 相似文献
948.
综合工程物探在上海地铁四号线抢险工程中的应用 总被引:3,自引:0,他引:3
在上海地铁四号线抢险工程中,综合工程物探快速、准确地圈定了受地面沉降影响,周边土体的扰动范围及深度,并对江底隧道的状况进行了调查。文章介绍了用地质雷达、高分辨率SH波浅层反射波法、瞬态瑞雷面波法勘探及水上高密度多波列地震影像法等综合工程物探方法在该工程中的应用前提及效果。 相似文献
949.
依托ARC/INFO平台,把湖北省近四十年所发生的地震的震中、震级及发震时间从文字记录信息转化为直观的并具有大地坐标的空间点位信息;利用平台功能强大的编辑模块和空间分析等功能对地震数据进行处理分析研究,并在此基础上结合ARCVIEW的桌面制图优点绘制基本图件完成输出与查询。该过程是湖北省区域稳定性评价的重要数据准备,同时也为湖北省地壳稳定性评价提供一个重要的评价因子。 相似文献
950.
Lead isotopes have been widely applied in geochemical exploration and evaluation of ore deposits, as well as in ascertaining the age of mineralization and the source of ore fluids.Long-term practice showed that the method of lead isotope targeting is somewhat efficient for macroscopic evaluation of forecasting areas, but not powerful enough for for ecasting concealed orebodies. As the contents of U and the variation of U/Pb ratio sharply decrease with depth in the lithosphere, U-Th-Pb isotopic differentiation must have occurred during the crust-mantle e-volution. Lead isotopic ratios show a wide variation range, varying in the front of mineralizationand shallow-derived ores, but maintaining very stable in the major orebody and being usuallyclose to the average isotopic composition of the crust and mantle of the continent block fromwhich the ores were derived. Therefore, the lead isotopic composition can serve as a measure for identifying the position of mineralization. The lead isotope geochemistry was applied to the ex-ploration and evaluation of the Baoban gold deposits of Hainan Province, China. The an alyticalresults of ore veins and adjacent rocks showed that there is a correlation between the lead isotopedata and the position of orebody. Based on the experience from the Baoban gold deposits and other ore deposits in Yunnan Province, an exploration principle has been established, that is,positive anomalies of lead isotope eigenvectors for prospecting deep-seated orebodies and nega-tive anomalies of eigenvectors for enlarging lateral exploration surrounding the known deposit.The ore beds in the Erjia and Beiniu mining districts should be as signed to the deep part of the orebody and those in the Tuwaishan mining district should be the shallow part, so ore beds cor-responding to those in the Erjia and Beiniu mining districts may be found in the Tuwaishan min-ing district. 相似文献