全文获取类型
收费全文 | 42篇 |
免费 | 10篇 |
国内免费 | 18篇 |
专业分类
测绘学 | 3篇 |
大气科学 | 9篇 |
地球物理 | 24篇 |
地质学 | 19篇 |
海洋学 | 9篇 |
天文学 | 1篇 |
综合类 | 1篇 |
自然地理 | 4篇 |
出版年
2022年 | 3篇 |
2021年 | 4篇 |
2020年 | 7篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 3篇 |
2016年 | 4篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2013年 | 6篇 |
2012年 | 3篇 |
2011年 | 1篇 |
2010年 | 2篇 |
2008年 | 4篇 |
2007年 | 1篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2004年 | 2篇 |
2001年 | 1篇 |
2000年 | 3篇 |
1999年 | 5篇 |
1998年 | 2篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 2篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1985年 | 1篇 |
1981年 | 1篇 |
排序方式: 共有70条查询结果,搜索用时 15 毫秒
41.
盆地的环境地质记录是从盆地的形成、发展演变、沉积物形成的地球化学与古气候环境、沉积物堆积后所经历的压实、成岩来加以研究的.除无机介质(矿物)外的有机质,在成岩压实受热过程中化学成分与结构的变化,也是盆地环境地质记录的一部分,环境地质研究的归宿是对矿产-化石燃料形成与潜能的估价,完整的研究应该包括化石燃料形成(成烃成煤)环境及成藏(保存)环境等.对云南滇西陇川、瑞丽及保山等三个新生代断陷盆地环境地质记录的研究揭示,在极其相似的盆地形成演变、沉积地球化学与古气候、成岩与成烃背景基础上,化石燃料的形成与潜能在三个盆地具有差异性;指出陇川盆地以找寻煤型气及初熟(低熟)油为主,保山盆地以寻找浅部生物成因气及煤型气为主,瑞丽盆地相对潜能较差,仅有生物气浅部产出的可能. 相似文献
42.
A global eddy-permitting ocean-ice coupled model with a horizontal resolution of 0.25 by 0.25 is established on the basis of Modular Ocean Model version 4 (MOM4) and Sea Ice Simulator (SIS). Simulation results are compared with those of an intermediate resolution ocean-ice coupled model with a horizontal resolution of about 1 by 1 . The results show that the simulated ocean temperature, ocean current and sea ice concentration from the eddy-permitting model are better than those from the intermediate resolution model. However, both the two models have the common problem of ocean general circulation models (OGCMs) that the majority of the simulated summer sea surface temperature (SST) is too warm while the majority of the simulated subsurface summer temperature is too cold. Further numerical experiments show that this problem can be alleviated by incorporating the non-breaking surface wave-induced vertical mixing into the vertical mixing scheme for both eddy-permitting and intermediate resolution models. 相似文献
43.
Wang Xiaoyan Yang Tao Xu Chong-Yu Xiong Lihua Shi Pengfei Li Zhenya 《Natural Hazards》2020,104(2):1239-1258
Natural Hazards - Glaciers are important freshwater storage systems in the Tianshan Mountains. Under the context of climate change, quantifying changes in glacier mass balance, the melt-season... 相似文献
44.
Water vapor transport and cross-equatorial flow over the Asian-Australia monsoon region simulated by CMIP5 climate models 总被引:1,自引:0,他引:1
The summer mean water vapor transport (WVT) and cross-equatorial flow (CEF) over the Asian-Australian monsoon region simulated by 22 coupled atmospheric-oceanic general circulation models (AOGCMs) from the World Climate Research Programme’s Coupled Model Intercomparison Project Phase 5 (CMIP5) were evaluated. Based on climatology of the twentieth-century simulations, most of models have a reasonably realistic representation of summer monsoon WVT characterized by southeast water vapor conveyor belt over the South Indian Ocean and southwest belt from the Arabian Sea to the East Asian. The correlation coefficients between NCEP reanalysis and simulations of BCC-CSM1-1, BNU-ESM, CanESM2, FGOALS-s2, MIROC4h and MPI-ESM-LR are up to 0.8. The simulated CEF depicted by the meridional wind along the equator includes the Somali jet and eastern CEF in low atmosphere and the reverse circulation in upper atmosphere, which were generally consistent with NCEP reanalysis. Multi-model ensemble means (MME) can reproduce more reasonable climatological features in spatial distribution both of WVT and CEF. Ten models with more reasonable WVT simulations were selected for future projection studies, including BCC-CSM1-1, BNU-ESM, CanESM2, CCSM4, FGOALS-s2, FIO-ESM, GFDL-ESM2G, MRIOC5, MPI-ESM-LR and NorESM-1M. Analysis based on the future projection experiments in RCP (Representative Concentration Pathway) 2.6, RCP4.5, RCP6 and RCP8.5 show that the global warming forced by different RCP scenarios will results in enhanced WVT over the Indian area and the west Pacific and weaken WVT in the low latitudes of tropical Indian Ocean. 相似文献
45.
广义线性统计降尺度方法模拟日降水量的应用研究 总被引:3,自引:2,他引:1
利用1960—2010年青藏高原23个台站和长江下游25个台站的日降水量观测资料及NCEP再分析资料,采用广义线性模型的统计降尺度方法模拟台站日降水量,并评估了广义线性模型对日降水量的模拟能力。在建模期(1960—2005年)广义线性模型对日降水量表现出良好的模拟能力,两区域模拟结果与观测值1月平均相关系数0.75左右,7月也均超过0.5。模拟结果大部分台站日降水偏大,但偏大的量值较小;模拟的无降水准确率较高,最高值在高原区域,1月平均达85.2%。检验期(2006—2010年)广义线性模型模拟的日降水与建模期具有较好的一致性。此外,对两区域代表站的分析显示,广义线性模型模拟降水极值和降水0值的效果较好,且较好地还原了主要降水过程。总之,广义线性模型对日降水量的降尺度效果良好,适合应用于气候领域的相关研究。 相似文献
46.
Tianjun Zhou Ziming Chen Liwei Zou Xiaolong Chen Yongqiang Yu Bin Wang Qing Bao Ying Bao Jian Cao Bian He Shuai Hu Lijuan Li Jian Li Yanluan Lin Libin Ma Fangli Qiao Xinyao Rong Zhenya Song Yanli Tang Bo Wu Tongwen Wu Xiaoge Xin He Zhang Minghua Zhang 《Acta Meteorologica Sinica》2020,34(1):1-19
The Earth-Climate System Model (ECSM) is an important platform for multi-disciplinary and multi-sphere integration research, and its development is at the frontier of international geosciences, especially in the field of global change. The research and development (R&D) of ECSM in China began in the 1980s and have achieved great progress. In China, ECSMs are now mainly developed at the Chinese Academy of Sciences, ministries, and universities. Following a brief review of the development history of Chinese ECSMs, this paper summarized the technical characteristics of nine Chinese ECSMs participating in the Coupled Model Intercomparison Project Phase 6 and preliminarily assessed the basic performances of four Chinese models in simulating the global climate and the climate in East Asia. The projected changes of global precipitation and surface air temperature and the associated relationship with the equilibrium climate sensitivity under four shared socioeconomic path scenarios were also discussed. Finally, combined with the international situation, from the perspective of further improvement, eight directions were proposed for the future development of Chinese ECSMs. 相似文献
47.
中国陆地生态敏感性时空演变特征 总被引:5,自引:0,他引:5
生态敏感性作为评价区域生态环境问题的重要指标之一,对区域的生态治理与管理工作具有重要意义。本文从自然生态系统、自然—社会复合生态系统、社会生态系统等视角选取生物多样性、水热环境、土壤盐渍化、土地荒漠化、土壤侵蚀和人类干扰6个指标,运用全排列多边形图示指标法对2000—2018年间中国陆地生态敏感性进行计算,并运用格网编码法对其时空演变特征进行分析。研究结果表明:① 2000—2018年间中国陆地生态敏感性总体稳定,生态敏感值稳定在0.33~0.34之间;但得益于21世纪以来中国实施了一系列生态环境治理与预防工作,敏感值在2000—2018年间持续下降,表明中国陆地生态敏感性状况正在逐渐好转。② 中国陆地生态敏感性空间异质性显著,呈现出“东低西高、南低北高”“城区高、郊区低”的空间分布格局。中国西部区域和北方区域自然环境恶劣,生态自我调节能力较差,易受外界因素的影响,而人类聚居区生态自我调节能力虽然较强,但由于人类活动强度较大,其敏感性反而较高。③ 中国陆地生态敏感性受土壤(地)环境因素影响较大,但人类干扰因素影响力也在逐年递增,这表明在经济快速发展的同时,中国的生态环境保护与治理工作仍然任重道远。 相似文献
48.
关于经验性地震预报问题的思考 总被引:1,自引:0,他引:1
从科学认识活动的发展历程,特别是从科学观测性质两个方面论证了经验性预报存在的必然性和必要性,同时指出,只有将第三类观测提升为第二类观测才能真正实现物理预报。 相似文献
49.
A series of model experiments was performed in an ultrasonic laboratory to study the radiation of downhole sources in a variety of formations. Three models were used in the experiments. They were a Lucite model, a Lucite model with a free glass pipe in the centre, and a glass-cased soil model. In addition, a finite-difference modelling technique was used to simulate the wave propagation in these models and the results of the laboratory and numerical experiments are compared. In the Lucite borehole model the waveforms recorded in the experiment agree very well with the finite-difference synthetics. The snapshots of the wavefield from the finite-difference simulation show the radiation pattern of the P- and S-waves in the Lucite formation. These patterns are consistent with the theoretical calculations. In the Lucite model with the free glass pipe, the finite-difference synthetics are also in good agreement with the experimental observations, especially for the conical P-wave arrival. The angle between the wavefront of the conical P-wave and the borehole axis, observed from the snapshot, agrees with the theory. In the cased soil model, the arrival time of the finite-difference synthetics is in good agreement with the laboratory measurements. The relative amplitudes of the P-wave and the Mach wave are not correctly modelled because intrinsic attenuation is not included in the finite-difference calculation. The Mach cone angle from the snapshot agrees with the theoretical prediction. Finally, a finite-difference method was used to simulate Mach-wave propagation in a formation with two horizontal layers. In the case of two slow layers, the Mach-wave generated in the first layer is reflected back from and transmitted through the boundary and another Mach wave is generated at the second layer when the Stoneley wave travels into the second layer. In the case of a formation having one slow and one fast layer, the Mach wave generated in the slow layer is reflected back at the boundary and leaked into the fast layer. There is no Mach wave in the fast layer. 相似文献
50.