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81.
几种鱼类培养细胞对不同干扰素敏感性的研究 总被引:5,自引:0,他引:5
本文研究了四种鱼类培养细胞CIK、CAB、GCB、BRE对Huifn-a,CIK、CAB、GCB、GRE、FHM等五种鱼类培养细胞干扰素作用的敏感性。这四种鱼类培养细胞对HuIFN-a不敏感,对五种鱼类培养细胞干扰素表现出相对一致的敏感性差异,其中GRE细胞对鱼类干扰素最敏感,其次为CAB、GCB。CIK细胞能产生高滴度的干扰素但对鱼类干扰素不敏感。不同病毒对干扰素作用的敏感性也不同。 相似文献
82.
孟加拉湾风暴Mala登陆期间地形敏感试验 总被引:1,自引:0,他引:1
孟加拉湾是全球8个热带气旋易发生的地区之一。孟加拉湾风暴向偏北和偏东方向移动,会对中国青藏高原和西南地区形成重大影响,而孟加拉湾风暴的移动方向受到青藏高原和云贵高原大地形的影响很大。为了分析大地形对孟加拉湾风暴路径、结构变化和降水分布的作用和影响,文中利用WRF模式对2006年4月29—30日孟加拉湾风暴Mala的登陆过程进行数值模拟研究。试验结果表明:模拟风暴中心的路径和强度与实况虽有一定误差,但移动趋势均为东北方向,强度误差较小,表明WRF模式对本个例的模拟可以参考。通过不同地形高度敏感试验,分析风暴在登陆前后分别在全地形、半地形和零地形高度情况下的移动路径和速度、环流结构、动力结构以及在云南省产生的降水分布和强度。结果表明:风暴登陆前,大地形对风暴结构有间接影响,使高层出现倾斜。在风暴登陆过程中,地形的阻挡和摩擦作用能较明显影响风暴的移动路径和速度。风暴登陆后,地形抬升使风暴强度减弱,移动速度加快;结构由基本对称变为非对称,且斜压结构明显。地形对降水存在双重作用,一方面地形抬升使风暴产生的降水增加,另一方面地形摩擦使风暴强度减弱从而减少降水。 相似文献
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Dirk Böhme 《Limnologica》2011,41(2):80-89
Induced by a brine discharge study for a submerse gas storage cavern project, a suitable methodology for rapid impact assessment had to be found. In this paper a simple stochastic, stationary model is described for assessment of intensity and temporal variability of chloride pollution at the regional scale of the rivershed. Chloride concentration is used as a proxy of salinity. It is assumed to be the result of deterministic process (flow-dependent) and stochastic variation (estimated for boundary conditions and tributaries by an additive error term based on PERT distribution). This approach is suited to conduct Monte Carlo simulations in order to calculate long-time means and percentiles of the prospective in-stream chloride concentration (exposure model). The biocoenoses exposed to this pollution has to be evaluated in terms of chloride tolerance. Herefore Maximum Field Distributions (MFD) of relevant species (aquatic macrophytes, macroinvertebrates, fish) were compiled and merged to Species Sensitivity Distributions (SSDs). Critical aspects of MFD data quality are discussed. Chloride model simulations representing different discharge scenarios provide exposure parameters (e.g. 90th percentile) that can be compared with SSD-derived protection levels (e.g. maximum loss of 10% of taxa) to quantify and evaluate possible adverse effects as well as potential recolonisation in case of load removal. Crosslinks to conservation issues are relevant in the selection and position of rare or protected species in the SSD. As an analysis of the German legal framework and technical guidelines revealed lack of guidance and best practices for such assessment and impact evaluation, recent experience highlights serious needs in applied research. 相似文献
86.
SPT-N-based methods have been adopted for liquefaction assessment of soils during earthquakes for decades. However, there has not been a consistent way of assessing the accuracy and applicability of these methods. The Chi-chi earthquake of 1999, which has been the most serious ground shaking in Taiwan within the century, caused extensive liquefactions in mid-west alluvial deposits of the island. This paper assesses the prediction accuracy of several SPT-N-based methods using liquefaction and non-liquefaction incidents observed during the earthquake. A sensitivity study on commonly adopted parameters shows that the SPT blow count and peak ground acceleration are most sensitive in computing liquefaction potential. By comparing the error in predicting liquefaction and non-liquefaction incidents, this study concludes that Tokimatsu and Yoshimi’s method is more accurate than the other methods. However, the differences between prediction errors of various methods are minimal, indicating all of the methods examined are applicable for the 1999 earthquake in Taiwan. 相似文献
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横断山区近代气候变化的研究 总被引:6,自引:1,他引:5
横断山地处我国西南的藏东、川西和滇西北一带,境内地形复杂,平均海拔在3000米以上。长期以来,由于资料短缺,对该地区历史时期气候变化研究甚少。经实地考察,作者获取若干树木年轮标本,辅以其它类型资料,对该地区最近数百年来的温度、降水变化及气候类型演替,予以初步分析。并论及气候变化的振幅与周期性。 相似文献
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Using field data from Agnico-Eagle’s Meliadine gold project located in Nunavut Territory in northern Canada, a coupled DFN–DEM approach was used to evaluate the rock mass mechanical properties at REV. Variability in the structural data gathered on site and the variability associated with the stochastic modeling process have an impact on discrete fracture model (DFN) properties. Through a sensitivity analysis, this paper assesses the influence of a variation in the DFN model input parameters’ values on the rock mass peak properties – uniaxial compressive strength, Young modulus and Poisson ratio. The results not only highlight the possibilities associated with DFN–DEM modeling in characterizing rock mass properties at the engineering scale, they also provide a systematic way to assess the critical structural parameters controlling the rock mass properties. 相似文献