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641.
柴达木盆地那棱格勒河及其尾闾盐湖锂成矿物源:来自水化学和锶、硫同位素证据 总被引:2,自引:0,他引:2
柴达木盆地那棱格勒河尾闾盐湖(一里坪干盐滩、东台吉乃尔盐湖、西台吉乃尔盐湖和察尔汗盐湖别勒滩区段)赋存了我国目前最大的卤水锂矿床。那棱格勒河及其尾闾盐湖锂的物源仍存在一定争议,主要有围岩风化、古湖残留、含盐系地层淋滤、油田水、深部水等,目前缺乏有力的地球化学证据。本文系统采集了那棱格勒河流域及其尾闾盐湖不同水体样品16件,分析了其主、微量元素含量及锶、硫同位素组成。结合前人的研究成果,对区域水体中锂的来源进行了探讨,得出结论如下:那棱格勒河水锂含量(0.45~0.79 mg/L)比楚拉克阿拉干河支流(0.00~0.05 mg/L)高出一个数量级,其高锂含量主要受洪水河支流的补给;洪水河高锂含量与其上游热泉水的补给有关,该热泉水锂、锶含量高、87Sr/86Sr比值偏高,δ34S值偏低,与青藏高原典型热泉水地球化学特征(锂含量0.4~34.8 mg/L,锶含量0.07~4.24 mg/L,87Sr/86Sr比值0.71224~0.71259,δ34S值-10.... 相似文献
642.
The English version is improved carefully by Professor Zhong-Huai XU, Institute of Geophysics, SSB. 相似文献
643.
The response of the East China Sea (ECS) to a tropical cyclone (TC) is studied with a two-layernonlinear primitive equation ocean model. Numerica experiments indicate that there is rightward bias inocean response to a moving TC. The initial middle layer (ML) depth and stratification intensity havesubstantial impact on the Changes of SST and ML depth. The initial ML depth has large effect onthe value of the current, whereas the initial stratification intensity has slight influence on it. Thedistribution of ECS ML depth, especially the special ocean thermal structure on the continental shelf facil-itates the drop of SST. The simulation results of ocean response to Typhoon 7002 are fairly consistentwith the observation data. 相似文献
644.
煤层气藏的储集特征及储层评价 总被引:1,自引:0,他引:1
论述了煤层气非常规天然气的特征,指出控制煤储集性能的因素主要是煤岩性质、煤层埋藏深度及地质构造条件等,并综合分析了煤层气储层各种评价参数,指出各种有利于煤层气藏的地质条件和物性条件。 相似文献
645.
为提高短时强降水的监测和预警技术在山区等复杂地形中的应用,本文选取相关的探空资料分析天气背景,划分降水类型,与自动站订正技术相结合,采用Z-I分型最优化技术估测降水,利用交叉相关法对雷达反射率因子进行外推,并预测30min后的累积降水量。根据近3年的观测资料,制定出适合岳阳地区雷达反射率因子以及雷达估测降水对应的降水量级。通过与自动站雨量对比,Z-I分型最优化技术估测降水的相对误差较小;与Z-I经验公式估测降水对比分析,雷达估测降水的准确率有一定提高。经过岳阳示范区一年的实际应用表明:该方法对短时强降水的估测和预警均取得良好的效果,对强降水引起的山体滑坡等灾害具有一定的防范作用。 相似文献
646.
Fossil Taiwania was discovered from the Lower Cretaceous Yixian Formation of Lingyuan City, western Liaoning Province, Northeast China. It is identified as a new species, Taiwania lingyuanensis sp. nov.. The present specimen is preserved as impressions with well defined leaf shoots system and reproductive structures. Leaves are dimorphic, spirally and imbricately arranged. They are scale-like on the main and cone-bearing branchlets, and subulate to falcate-subulate on the juvenile or sterile shoots. The seed cones are singly elliptic, ovate or elongate-ovate and terminally borne on ultimate shoots, bearing 22–24 scale-bracts complexes imbricately and helically arranged around the cone axis, the bracts are broadovate, rhomboidal or hexagonal with entire margins. Both the leafy shoots morphology and reproductive structures are similar to extant Taiwania. Furthermore, geological distribution and molecular biological evidences support that Taiwania is probably originated from the eastern Asia at least in the Early Cretaceous and widely distributed in the North Hemisphere thereafter. 相似文献
647.
Wang Guixing Zhang Xiaoyan Sun Zhaohui Zhao Yaxian Du Wei Cui Jianbin Hou Jilun Wang Yufen 《中国海洋湖沼学报》2020,38(1):288-293
Journal of Oceanology and Limnology - Tetraploid fish are important for mass production of triploids in polyploid breeding. In this study, we reported a novel protocol for artificial induction of... 相似文献
648.
Journal of Oceanology and Limnology - Changes in the marine productivity and sedimentary environment since the last deglaciation in the Ross Sea are presented in this paper. Opal has replaced... 相似文献
649.
Shenghong Yang Wenjun Qu Yulong Tian Jiangfeng Chen Gang Yang Andao Du 《Chemical Geology》2008,247(3-4):401-418
Apparent Re–Os ages of some magmatic sulfide ore deposits are older than the zircon and baddeleyite U–Pb ages which are interpreted as the formation age of the host intrusions. The Jinchuan Ni–Cu–PGE deposit of China, the world's third largest, is such a case. We report apparent Re–Os isochron ages of 1117 ± 67 Ma, 1074 ± 120 Ma and 867 ± 75 Ma with initial 187Os/188Os ratios of 0.120 ± 0.012, 0.162 ±0.017 and 0.235 ± 0.027 for disseminated ores, sulfides from the disseminated ores and massive ores from Jinchuan, respectively. Using these data and Re–Os ages from the literature, we find that the oldest apparent Re–Os age and lowest initial Os isotope ratio are from disseminated ores which contain small amounts of sulfide minerals, the highest initial Os isotope ratios and youngest apparent Re–Os ages, consistent with the zircon and baddeleyite U–Pb ages, are from massive ores containing 90–100 modal% sulfide, and net-textured ores with about 25 modal% sulfides yield apparent Re–Os ages and initial Os ratios intermediate between those of the disseminated and massive ores.Because Os diffusion between sulfides is inhibited by the intervening silicates even at high temperatures, re-equilibration did not occur in the disseminated ore and the samples retained the Os ratios of the contaminated magma, leading to geologically meaningless ages that are older than the formation age of the rocks. While Os-bearing sulfide minerals and magnetite show low closure temperatures of Os diffusion and the sulfide minerals in the massive ore are closely connected with each other, facilitating fast diffusion of Os, re-equilibration of Os was achieved during cooling of the ore from about 850 °C after the segregation to about 400 °C. Thus, an age corresponding to the formation time and an elevated initial Os ratio were yielded by the massive ore. Os isotopes in the net-textured ore behave in the way intermediate between the disseminated and massive ores. Pb isotope data support the Os results. Disseminated ores have heterogeneous Pb isotope ratios whereas Pb in the massive ores is more uniform, consistent with Pb isotopic equilibration in the massive ores, but not in the disseminated ores. 相似文献
650.
Due to global warming, glaciers on the Tibetan Plateau(TP) are experiencing widespread shrinkage; however, the mechanisms controlling glacier variations across the TP are still rather unclear, especially on the northeastern TP. In this study, a physically based, distributed surface-energy and mass-balance model was used to simulate glacier mass balance forced by meteorological data. The model was applied to Laohugou No. 12 Glacier, western Qilian Mountains, China, during2010~2012. The simulated albedo and mass balance were validated and calibrated by in situ measurements. The simulated annual glacier-wide mass balances were-385 mm water equivalent(w.e.) in 2010/2011 and-232 mm w.e. in 2011/2012,respectively. The mean equilibrium-line altitude(ELA) was 5,015 m a.s.l., during 2010~2012, which ascended by 215 m compared to that in the 1970 s. The mean accumulation area ratio(AAR) was 39% during the two years. Climatic-sensitivity experiments indicated that the change of glacier mass balance resulting from a 1.5 °C increase in air temperature could be offset by a 30% increase in annual precipitation. The glacier mass balance varied linearly with precipitation, at a rate of130 mm w.e. per 10% change in total precipitation. 相似文献