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991.
PRE-ASSESSMENT OF EARTHQUAKE-INDUCED LOSSES BASED ON FIELD SURVEY AND KILOMETER GRID DATASET: A CASE STUDY FROM DEHONG DAI-JINGPO AUTONOMOUS PREFECTURE 下载免费PDF全文
The pre-assessment of earthquake damage based on field surveys and grid dataset in 1km resolution is very helpful for emergency preparedness and mitigation of earthquake disaster losses.In this paper,we briefly introduced the contents,principles,methods and the results of software assessment as well as the revised results after field surveys.In addition,the emergency supplies and manpower requirements after the outbreak of earthquake are discussed.The assessment contents include the earthquake affected area and population,the amount of casualties,injuries,economic losses,and the number of population to be resettled.Scenario earthquake is set with an interval of 50 kilometers along the major faults and the losses induced by earthquake are outputted by the software.After that,the software outputs are revised based on field surveys.In addition,according to the earthquake cases happening between 2008 and 2015,the growth curve model used to estimate the demand of rescue supplies and teams is also proposed in this study.Based on this model and the software named earthquake emergency disaster rapid assessment and dynamic visualized software (NIE Gao-zhong,2014),and with the help of the statistical data such as population density and socio-economic situations,earthquake losses are pre-assessed by taking Dehong Dai-Jingpo Autonomous Prefecture as an example.The comparison shows that the actual losses are nearly the same as the software outputs.However,due to the ignorance of the casualties caused by geological disasters,the revised casualties are more than the software output.Not only the study area discussed in this paper,the earthquake loss assessment method can also be used to other regions in China. 相似文献
992.
交错网格高阶差分解法是地震波场模拟的一种有效方法,这种方法的不足是时间和空间网格的离散,以差分代替微分模拟地震波场会引起数值频散.通量传输校正(FCT)方法能够有效地压制数值频散,将FCT方法与交错网格有限差分法相结合,可以提高波场模拟的精度和运算效率. 相似文献
993.
垂直梯度法是跃层示性特征计算中普遍使用的方法,但在某些情况下并不能很好地描述海洋要素的跃变特征.针对垂直梯度法的不足,引入水团分析中的最优分割法,对典型剖面,以及边界型、逆变型、多层型等几类特殊剖面的跃层边界分别进行了计算,并对垂直梯度法与垂直梯度法的计算结果进行了比较分析,结果表明最优分割法确定的跃层边界更为合理.通过对两种方法确定的中国近海温跃层的整体分布进行比较分析,证明了最优分割法能够弥补垂直梯度法在计算深海与浅海过渡区中的跃层时遇到的标准不匹配问题,较好地保持跃层的连续性. 相似文献
994.
Layers from one manganese nodule dredged from the Philippine Sea(16°56'N, 129°48'E; water depth, 5700 m) and 45 bulk nodules from offshore Minami-Torishima Island, Japan(23°3'N, 153°22'E; water depth, 1200 m) were analyzed chemically and their origin is discussed based on geochemical constraints. In general, Cu, Ni, Zn and Mo tend to increase with increasing Mn content, while Co, Pb, Ba, V, Sc, Th, and the rare earth elements(REEs) show less variation with increasing Mn content. Nodule 42 H from the Philippine Sea has an average Mn/Fe ratio close to 1 and shows a positive Ce anomaly, suggesting a predominant hydrogenous origin. Profiles of 230Th230 ex and Thex/232 Th ratios in the outer ~0.3 mm of nodule 42 H indicate a steady growth rate of ~1.7 mm/Myr. Nodule E30 from offshore Minami-Torishima is characterized by lower Mn, Fe, Mn/Fe(0.53) and Mo/V(0.2) ratios but higher P and Cu/Ni(0.31) ratio relative to other nodules from that area. The Ce content of E30 is unusually low(82 ppm) when compared with other nodules from the area and it is the only nodule analyzed with a negative Ce anomaly(-0.64). Based on the geochemical data we suggest that most nodules from offshore Minami-Torishima are primarily of hydrogenous origin except E30, which is dominated by hydrothermal input, and E45, which has about a 35% hydrothermal contribution. 相似文献
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999.
The spatial variability of streambed vertical hydraulic conductivity in an intermittent river, northwestern China 总被引:2,自引:0,他引:2
Leilei Min Jingjie Yu Changming Liu Juntao Zhu Ping Wang 《Environmental Earth Sciences》2013,69(3):873-883
Streambed vertical hydraulic conductivity (K) plays an important role in river water and groundwater interaction. The K at the ten transects (Ts1–Ts10) at the Donghe River (an intermittent river) in the Ejina Basin, northwestern China, was measured to investigate its spatial variation. Based on the sediment characteristics and vertical hydraulic conductivity of the riverbed, the entire riverbed of the Donghe River could be divided arbitrarily into two parts: an upper part (starting at Ts1 and ending at Ts9, without an obvious and continuous clogging layer) and a lower part (the remaining riverbed, with an obvious and continuous clogging layer). In the upper part, although the K varied with depth within the 0–30 cm layer, the variability with depth could be ignored in practice. The arithmetic mean K of the upper part ranged from 12 to 27.6 m/day, three orders of magnitude larger than that of the lower part (0.06 m/day). The change of K along the river cross section was significant, and larger values of K often occurred in the parts of the channels with greater water depth. However, there were no consistent patterns of the variability of K at transects across the river, which was influenced by the variation in streambed characteristics. The results could be useful for the estimation of groundwater recharge from river and groundwater resources evaluation in the Ejina Basin. 相似文献
1000.