全文获取类型
收费全文 | 300篇 |
免费 | 10篇 |
国内免费 | 5篇 |
专业分类
测绘学 | 8篇 |
大气科学 | 30篇 |
地球物理 | 89篇 |
地质学 | 109篇 |
海洋学 | 37篇 |
天文学 | 33篇 |
综合类 | 1篇 |
自然地理 | 8篇 |
出版年
2024年 | 2篇 |
2023年 | 1篇 |
2022年 | 3篇 |
2021年 | 5篇 |
2020年 | 5篇 |
2019年 | 8篇 |
2018年 | 17篇 |
2017年 | 8篇 |
2016年 | 20篇 |
2015年 | 13篇 |
2014年 | 17篇 |
2013年 | 14篇 |
2012年 | 24篇 |
2011年 | 29篇 |
2010年 | 21篇 |
2009年 | 25篇 |
2008年 | 18篇 |
2007年 | 15篇 |
2006年 | 7篇 |
2005年 | 10篇 |
2004年 | 4篇 |
2003年 | 4篇 |
2002年 | 6篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 2篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 1篇 |
1986年 | 1篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1983年 | 3篇 |
1982年 | 2篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1972年 | 1篇 |
1966年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有315条查询结果,搜索用时 15 毫秒
71.
72.
Stanko Ružičić Marta Mileusnić Kristijan Posavec Zoran Nakić Goran Durn Vilim Filipović 《水文研究》2016,30(22):4113-4124
The objective of this work was to build a prognostic water flow model and potentially toxic elements (lead, cadmium, zinc) transport model in the unsaturated zone. Research was conducted in the catchment area of Kosnica regional wellfield, where the unsaturated zone is characterised by Fluvisol. Lower sorption capacities were determined in the first horizons for all three potentially toxic elements. Correlation coefficient of the measured and simulated values of tracer concentration is 0.58 for the AC horizon and 0.84 for the 2C/C1 horizon. Based on calibrated water flow and transport parameters, a prognostic water flow model and potentially toxic elements (lead, cadmium, zinc) transport model in the unsaturated zone was built. In case of an accidental spill of potentially toxic elements with concentrations of 1000 mg/l, the risk of contamination of the aquifer is present. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
73.
Slope instability induced by volcano-tectonics as an additional source of hazard in active volcanic areas: the case of Ischia island (Italy) 总被引:1,自引:0,他引:1
Marta Della Seta Enrica Marotta Giovanni Orsi Sandro de Vita Fabio Sansivero Paola Fredi 《Bulletin of Volcanology》2012,74(1):79-106
Ischia is an active volcanic island in the Gulf of Naples whose history has been dominated by a caldera-forming eruption (ca.
55 ka) and resurgence phenomena that have affected the caldera floor and generated a net uplift of about 900 m since 33 ka.
The results of new geomorphological, stratigraphical and textural investigations of the products of gravitational movements
triggered by volcano-tectonic events have been combined with the information arising from a reinterpretation of historical
chronicles on natural phenomena such as earthquakes, ground deformation, gravitational movements and volcanic eruptions. The
combined interpretation of all these data shows that gravitational movements, coeval to volcanic activity and uplift events
related to the long-lasting resurgence, have affected the highly fractured marginal portions of the most uplifted Mt. Epomeo
blocks. Such movements, mostly occurring since 3 ka, include debris avalanches; large debris flows (lahars); smaller mass
movements (rock falls, slumps, debris and rock slides, and small debris flows); and deep-seated gravitational slope deformation.
The occurrence of submarine deposits linked with subaerial deposits of the most voluminous mass movements clearly shows that
the debris avalanches impacted on the sea. The obtained results corroborate the hypothesis that the behaviour of the Ischia
volcano is based on an intimate interplay among magmatism, resurgence dynamics, fault generation, seismicity, slope oversteepening
and instability, and eruptions. They also highlight that volcano-tectonically triggered mass movements are a potentially hazardous
phenomena that have to be taken into account in any attempt to assess volcanic and related hazards at Ischia. Furthermore,
the largest mass movements could also flow into the sea, generating tsunami waves that could impact on the island’s coast
as well as on the neighbouring and densely inhabited coast of the Neapolitan area. 相似文献
74.
75.
Ernesto Medina Marta Francisco Leonel Sternberg William T. Anderson 《Estuarine, Coastal and Shelf Science》2005,63(4):527-536
The 87Sr, 13C, and 15N isotopic signatures of organic matter in sediments from the continental shelf facing the Orinoco Delta were measured to determine the contribution of sediments transported from the Amazon River by the coastal Guayana current and the sediments transported by the Orinoco River. Box core samples between 60 and 300 m water depth collected along 4 transects located eastwards to the Orinoco Delta were analyzed. Carbon and nitrogen concentrations decreased with depth under water on the shelf, and were strongly correlated indicating homogeneity of organic matter composition. Phosphorus content was also associated to organic matter in most samples, but some of them revealed deposition of P-enriched sediments. The 87Sr/86Sr ratios showed a strong continental signature averaging 0.7117, therefore, limiting the possible carbon and nitrogen sources associated with these sediments to C3 trees, C4 grasses, or freshwater phytoplankton. The δ13C values were relatively high averaging −21‰, above values reported for sediments on the Amapá shelf and the Amazon River in Brazil. Average δ13C values did not differ significantly among transects. High δ13C values point to the influence of organic matter transported from the C4-plants dominated savannas in the northern fringe of the Orinoco River. δ15N values were positive and averaged 5‰, being within the range of values measured in the Marajo island (Amazon River) and the estuary of the Pará River. The δ15N values differed significantly among transects (4.9–5.2‰), lowest values corresponding to the northernmost transect near the coast of Trinidad, and the highest values corresponding to the transect located at the southernmost position. 相似文献
76.
77.
78.
Roberto Carniel Marta Tárraga Fausto Barazza Alicia García 《Bulletin of Volcanology》2008,70(9):1113-1121
Continuous seismic noise is recorded in the volcanic island of Tenerife (Canary Islands, Spain). The origin of this noise,
strongly augmented by anthropogenic contamination, is still under debate. In this paper, we discuss the relationship between
this noise and the occurrence of local tectonic events in the same area. In particular, transitions are sought in the time
evolution of dynamic parameters computed on the seismic noise, and examples are shown where abrupt transitions may be associated
with the occurrence of tectonic events. These transitions provide further evidence of the existence of a natural origin for
at least part of the seismic noise, which is strongly contaminated—if not dominated—by anthropogenic sources. 相似文献
79.
Marta Burgay Nanda Rea GianLuca Israel Andrea Possenti Luciano Burderi Tiziana Di Salvo Nichi D’Amico Luigi Stella Elisa Nichelli 《Astrophysics and Space Science》2007,308(1-4):531-534
We have performed deep searches for radio pulsations from four southern anomalous X-ray pulsars (AXPs) to investigate their
physical nature in comparison with the rotation powered pulsars. The data were acquired using the Parkes radio telescope with
the 1.4 GHz multibeam receiver. No pulsed emission with periodicity matching the X-ray ephemeris have been found in the observed
targets down to a limit of ∼0.1 mJy. A blind search has also been performed on all the 13 beams of the multibeam receiver
(the central beam being pointed on the target AXP), leading to the serendipitous discovery of two new radio pulsars and to
the further detection of 18 pulsars. Also a search for single dispersed pulses has been performed in the aim to detect signals
similar to those of the recently discovered rotating radio transients.
相似文献
80.
We use numerical simulations to investigate the evolution of sheath folds around slip surfaces in simple‐shear‐dominated monoclinic shear zones. A variety of sheath fold shapes develops under general shear, including tubular folds with low aspect ratio eye patterns and tongue‐like structures showing bivergent flanking structures in sections normal to the sheath elongation, which may potentially lead to confusing shear sense interpretations. Not all investigated monoclinic flow end‐members lead to the development of sheath folds sensu stricto (folds with apical angle <90°). The aspect ratio of the eye patterns, Ryz, correlates with the ratio between the principal strain in the Y‐direction and the smaller of the principal strains in the X–Z plane, and thus it could be used in strain analysis. 相似文献