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111.
1895-2016年全球海运网络中的海峡两岸港口运输联系变化 总被引:2,自引:0,他引:2
台湾地区与中国大陆隔海相望,海上运输是两岸间货物往来的最主要方式。受国际政治和贸易模式的影响,从19世纪中后期以来,两岸港口运输联系变化剧烈。利用劳合社(Lloyd's)1895-2016年两岸港口间航线的O-D数据,从国家层面和全球层面研究海峡两岸港口运输联系的变化。主要结论为:① 近代开埠至割让给日本之前,台湾地区与大陆的海运联系紧密,厦门港是台湾地区最重要的中转港;日据之后,台湾地区成为日本的原料来源地和商品销售地,台湾地区—日本—中国大陆形成三角运输联系;两岸对峙后,两岸港口运输联系切断,台湾地区—美国—日本形成三角贸易网络;1979年后,香港港成为两岸运输联系的最重要中转港,两岸直航后,台湾地区与大陆间的港口运输联系在广度和深度上不断拓展。② 台湾地区区位优势明显,但由于是海岛,陆向腹地狭小,因此充分利用区位优势和地缘优势,把区域经济增长中心作为自身的海向腹地,以形成紧密的海上运输联系是台湾地区经济持续发展的关键。改善与中国大陆之间的关系、分享中国大陆发展的机遇、推动海峡两岸的港口运输联系是台湾地区的“天时”与“人和”。 相似文献
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Cesar Azorin-Molina Sander Tijm Deliang Chen 《Theoretical and Applied Climatology》2011,106(3-4):531-546
We present an automated and manual algorithm for identifying past sea breeze episodes in the Bay of Alicante (southeastern coast of the Iberian Peninsula, IP, Spain) for a 6-year study period (2000–2005). The main goal was to provide databases for better understanding the functioning of sea breezes, which have a crucial influence on weather and climate in both coastal and inland areas and therefore affect human life in many ways. The algorithms apply a well-defined set of criteria based on meteorological and sea surface temperature measurements in order to detect past occurrences. The automated and manual identification techniques successfully identified a total of 475 and 1414 sea breeze events, respectively. A large database containing the significant characteristic parameters measured (onset time, cessation time, duration time, maximum wind speed, inland penetration, etc.) for these 475 sea breeze days is presented. We evaluated the accuracy of both selection techniques by means of comparison with independent objective and subjective techniques. Both databases are the major contribution of this paper and have been used in some climatological sea breeze studies and are also presented here for any coastal expert interested in numerical–theoretical, observational–experimental and climatological wind studies. 相似文献
113.
Both magmatic Ni–(Cu) and hydrothermal iron oxide–copper–gold mineralization coexist in ancient belts but their relationship remains poorly known. Geochronology and field geology evidence show that in SW Iberia both styles of mineralization were coeval with widespread metaluminous to peraluminous Variscan magmatism (350–330 Ma). We propose that mineralization was probably related to a hidden large layered mafic–ultramafic layered complex, recently inferred from geophysics, that was emplaced in a mid-crustal decollement zone. Contamination of a primitive mantle-derived magma with continental crust in the layered complex led to fractional crystallization accompanied by high-T–low-P metamorphism and the incorporation of volatiles into the melt. Hot hypersaline CO2–CH4-bearing brines were subsequently released and focused along major thrusts and strike-slip faults to produce the IOCG mineralization. Assimilation of continental crust also led to the formation of sulphide magmas that were tectonically injected high into the crust, leading to the formation of pipe-like breccia-hosted Ni–(Cu) ore bodies. All these processes took probably place as a consequence of oblique ridge– and/or continent–continent collision. 相似文献
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Antonio Maldonado Cesar Méndez Paula Ugalde Donald Jackson Roxana Seguel Claudio Latorre 《第四纪科学杂志》2010,25(6):985-988
The brief, terminal Pleistocene archaeological site at Santa Julia (SJ, 31° 50′ S; 71° 45′ W) is the only one with fluted projectile preforms and megafauna consumption known from the Chilean semiarid coastline. Here, we present the climatic history at SJ during the early Holocene reconstructed from pollen and charcoal analyses spanning 13.2–8.6 ka (=103 calibrated 14C yr BP). Elevated charcoal concentrations confirm human activity by 13.2 ka. Human occupation decreased in intensity and charcoal practically disappears from the record after 10.6 ka, followed by wetland expansion at SJ between 10.5 and 9.5 ka. Local dominance of coastal shrubland reveals that dry phases occurred between >11.2–10.5 and 9.5–9.0 ka. Overall, these findings imply that by modulating available resources at both local and landscape levels climate change may have played an important role in explaining the peopling of semiarid coastal Chile. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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A system identification approach can be incorporated in groundwater time series analysis, revealing information concerning the local hydrogeological situation. The aim of this work was to analyse water table fluctuations in an outcrop area of the Guarani Aquifer System (GAS) in Brotas/SP, Brazil, using data from a groundwater monitoring network. The water table dynamic was modelled using continuous time series models that reference the hydrogeological system upon which they operate. The model’s climatological inputs of precipitation and evapotranspiration generate impulse response (IR) functions with parameters that can be related to the physical conditions concerning the hydrological processes involved. The interpretation of the model parameters from two sets of monitoring wells selected at different land-use sites is presented, exemplifying the effect of different water table depths and the distance to the nearest drainage location. Systematic trends of water table depths were also identified from model parameters at specific periods and related to plant development, crop harvest and land-use changes.
EDITOR D. KoutsoyiannisASSOCIATE EDITOR L. Ruiz 相似文献
118.
Julio Cesar Wasserman Ana Maria G Figueiredo Fabio Pellegatti Emmanoel V Silva-Filho 《Journal of Geochemical Exploration》2001,72(2):1013
The geochemistry of Sepetiba Bay was studied in four sediment cores using a multi-element approach. Two cores were sampled in the more contaminated eastern part of the bay and two cores were sampled in the western region. The aim was to determine whether less common elements like the rare earths or the actinides are associated with contaminant metals like zinc in the Bay. Samples were analysed by instrumental neutron activation analysis that permits the quantification of total concentrations of metals (Ba, Co, Cr, Cs, Fe, Hf, Rb, Sc, Zn), rare earth elements (Ce, Eu, La, Lu, Sm and Yb), actinides (Th, U), non-metals and semi-metals (As, Br). Organic carbon and total sulphur were also analysed. The results show very strong zinc contamination in the top layers (more than 1000 μg g−1) and background concentrations in the bottom (15 μg g−1). Elements like chromium which would be expected to be released by the heavy industries of Sepetiba Bay, did not show a contamination profile, and concentrations remained close to those of natural environments. No evidence of any association between the zinc and other potential contaminant elements could be identified in this work. 相似文献
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