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141.
Laura K. Siebeneck Michael K. Lindell Carla S. Prater Hao-Che Wu Shih-Kai Huang 《Natural Hazards》2013,65(3):2267-2286
Managing evacuees’ reentry into their communities after an evacuation can be a major challenge for emergency managers, especially in instances when evacuees return before the official all-clear message. Despite the frequency of post-evacuation reentry into evacuated areas, there have been few studies of this process and the issues returnees expect and experience during the return phase. A survey of evacuees after Hurricane Ike indicates that household compliance with reentry plans was low, with only a minority of returnees (38 %) complying with official reentry plans. An examination of reentry concerns shows that minority ethnicity, lower education, and lower income were associated with higher levels of reentry concerns and, to a lesser extent, with problems experienced after returning. Results also indicate that none of the demographic variables correlated significantly with compliance with official reentry plans and only higher income predicted later entry. However, concerns about reentry traffic predicted earlier reentry and concern about physical risk was related to reentry plan compliance. This study provides insight into the concerns that motivate households’ reentry decisions and can inform the creation of return strategies that account for people’s concerns about their hurricane-impacted communities. 相似文献
142.
Carla Braitenberg Patrizia MarianiLavinia Tunini Barbara GrilloIldikò Nagy 《Journal of Geodynamics》2011
Our goal is to determine vertical crustal movement rates from tide gauge and satellite altimetry measurements. Tide gauges measure sea level, but as they are fixed to the crust, they sense both sea surface height variations and vertical crustal movements. The differential sea level rates of sufficiently nearby stations are a good means to determine differential crustal movement rates, when sea level height variations can be assumed to be homogeneous. Satellite altimetric measurements determine sea surface height variations directly and can be used to separate the crustal signal from the sea surface height variations in tide gauge measurements. The correction of the tide gauge sea level rates for the sea surface height contribution requires collocation of the satellite pass and the tide gauge station. We show that even if this is not the case, the satellite altimetric observations enable correction of differential tide gauge rates for the effects of sea surface rate inhomogeneities. 相似文献
143.
Carla G. B. Brenner Carlos A. Mallmann Daniel R. Arsand Francieli M. Mayer Ayrton F. Martins 《洁净——土壤、空气、水》2011,39(1):28-34
In this work, an analytical methodological study was carried out to determine the antimicrobials sulfamethoxazole and trimethoprim, as well as their metabolites, in hospital effluent. The determinations were conducted by liquid chromatography tandem mass spectrometry using a hybrid triple quadrupole‐linear ion trap mass spectrometer (LC‐QqLIT‐MS). The data acquisition was made in selected reaction monitoring (SRM) mode, in which two SRM transitions were monitored to ensure that the target compounds were accurately identified by the information dependent acquisition (IDA) function. The limits of detection (LOD) and quantification (LOQ) were 0.25 and 0.80 µg L?1 for sulfamethoxazole and 0.15 and 0.50 µg L?1 for trimethoprim. The linear range for the SMX was 0.8–100.0 µg L?1 and TMP was 0.5–100.0 µg L?1 on the basis of six‐point calibration curves generated by means of linear regression analysis. The coefficients of the correlation were higher than 0.999, which ensured the linearity of the method. The average concentration of sulfamethoxazole and trimethoprim found in hospital effluent was 27.8 and 6.65 µg L?1, respectively. The analytical methodology employed allowed two metabolites to be identified, N4‐acetyl‐sulfamethoxazole and α‐hydroxy‐trimethoprim. Fragmentation pathways were proposed. 相似文献
144.
Cadmium, Co, Cu, Ni and Pb adsorption is measured on montmorillonite as a function of pH (3–11), ionic strength (0.001–0.1 M NaNO3), and sorbate concentration (0.1–10 μM metal on 0.5 g/L solid). Sorption of all metals shows strong dependence on ionic strength and sorbate concentration, as well as a break in the slope of the edge, indicative of a 2-site interaction with montmorillonite. The resulting adsorption edges are used to parameterize diffuse layer surface complexation models (DLMs) for each metal. A 2-site DLM with a bidentate variable charge surface hydroxyl site and a bidentate permanent charge exchange site produced good fits for the individual experiments, but lacked the robustness to accurately predict adsorption across the entire experimental range. Other models, such as CCM, TLM, or CD-MUSIC may be required for more accurate predictions across broad ranges of solution conditions. 相似文献
145.
Nathaniel A. Barnes Alan E. Kehew R. V. Krishnamurthy Carla M. Koretsky 《Environmental Earth Sciences》2011,62(5):1027-1038
High iron concentrations create water quality problems for municipal use in glacial drift aquifer units. The chemical evolution
of oxic groundwater in shallow aquifer units to anoxic groundwater in deeper aquifer units, in which soluble Fe(II) is stable,
is attributed to coupled reduction of Fe(III) on aquifer solids with oxidation of organic carbon. The objective of this study
was to characterize the distribution of organic carbon in aquifer and aquitard sediments to determine the availability of
potential electron donors to drive these reactions. To do this, four complete rotasonic cores in a glacial aquifer/aquitard
system were sampled at close intervals for analyses of grain-size distribution and organic carbon content. The results indicate
significantly higher organic carbon concentrations in diamicton (till) units that function as aquitards, relative to coarse-grained
aquifer units. In addition, readily reducible iron content in the diamicton units and lower aquifer unit materials is sufficient
to produce far more dissolved iron than is present in the aquifer. Groundwater evolves to the level of iron reduction as a
terminal electron-accepting process as it moves downward through aquitard units along flow paths from upland recharge areas
to downgradient discharge areas. Deeper aquifer units are therefore unlikely to contain groundwater with low iron concentration. 相似文献
146.
Sabrina Y. Fazzito José M. Cortés Augusto E. Rapalini Carla M. Terrizzano 《International Journal of Earth Sciences》2013,102(5):1447-1466
The geometry and related geomorphological features of the right-lateral strike-slip El Tigre Fault, one of the main morphostructural discontinuities in the Central–Western Precordillera of Argentina, were investigated. Achievements of this survey include: recognition of structural and geometrical discontinuities along the fault trace, identification and classification of landforms associated with local transpressional and transtensional sectors, observation of significant changes in the fault strike and detection of right and left bends of different wavelength. In the Central Segment of the El Tigre Fault, 2D electrical resistivity tomography surveys were carried out across the fault zone. The resistivity imaging permitted to infer the orientation of the main fault surface, the presence of blind fault branches along the fault zone, tectonic tilting of the Quaternary sedimentary cover, subsurface structure of pressure ridges and depth to the water table. Based on this information, it is possible to characterize the El Tigre Fault also as an important hydro-geological barrier. Our survey shows that the main fault surface changes along different segments from a high-angle to a subvertical setting whilst the vertical-slip component is either reverse or normal, depending on the local transpressive or transtensive regime induced by major bends along the trace. These local variations are expressed as sections of a few kilometres in length with relatively homogeneous behaviour and frequently separated by oblique or transversal structures. 相似文献
147.
Claudio Zanolla Carla Braitenberg Jrg Ebbing Marcello Bernabini Kurt Bram Gerald Gabriel Hans-Jürgen Gtze Salvatore Giammetti Bruno Meurers Rinaldo Nicolich Franco Palmieri 《Tectonophysics》2006,414(1-4):127
The deep seismic profile Transalp crosses, from north to south, Germany, Austria and Italy. The gravity measurements for each country were made by national agencies with different reference systems and data reduction methods. Within the frame of the Transalp-project a comprehensive database of the Eastern Alps was compiled covering an area of 3.5° by 4° in longitude and latitude (275 by 445 km), respectively. To increase the data coverage in the south Alpine area two gravity surveys were carried out, resulting in 469 areally distributed new stations, of which 215 have been measured with the intent to improve the geoid in the area of the planned Brenner Basistunnel (BBT). The resulting gravity database is the best in terms of resolution and data quality presently available for the Eastern Alps. Here the free air, Bouguer and isostatic gravity fields are critically discussed. The spatial density of existing gravity stations in the three countries is discussed. On the Italian side of the Alps the spatial density is rather sparse compared to the Austrian side. The Bouguer-gravity field varies between − 190 * 10− 5 m/s2 and + 25 * 10− 5 m/s2, with the minimum located along the Alpine high topographic chain, but with a small offset (a few tens of km) to the greatest topographic elevation, showing that the Airy-type local isostatic equilibrium does not fully apply here. The maximum of the Bouguer anomaly has an elongated shape of 100 by 50 km located between the towns of Verona and Vicenza and covers the Venetian Tertiary Volcanic Province (VTVP), a feature not directly related to the plate collision in the Eastern Alps. The gravity high is only partly explainable by high-density magmatic rocks and requires also a deeper source, like a shallowing of the Moho. The isostatic residual anomalies (Airy model) are in the range ± 50 * 10− 5 m/s2, with the greatest positive anomaly corresponding to the location of the VTVP, indicating here under-compensation of masses. At last a discussion of a 2D density model based on reflection seismic data and receiver functions is made. 相似文献
148.
Graciano P. Yumul Carla B. Dimalanta Edanjarlo J. Marquez Karlo L. Queaño 《Journal of Asian Earth Sciences》2009,34(5):610-623
The collision of the Palawan microcontinental block with the Philippine mobile belt had significantly influenced the geological evolution of the Philippines. Multiple collisions involving several fragments, through space and time, resulted into the collage of terranes of varying origin exposed in this part of central Philippines. Cusping of the overriding plate, volcanic arc gap, ophiolite emplacement, incipient back-arc rifting, island rotation and tilting, raised coastal terraces, metamorphism, intrusion of igneous rocks and steepened subducted slab as seen in focal mechanism solutions are some of the manifestations of this collision. A late Early Miocene to early Middle Miocene age (20–16 Ma) is proposed for the major collision between the Palawan indenter and the Philippine mobile belt. The collision boundary is located from the northern part of Mindoro through the central mountain range swinging east of Sibuyan Island in the Romblon Island Group and finally threading along the Buruanga Peninsula and eastern side of the Antique Ophiolite Complex before exiting and connecting with the Negros Trench. The collision, through accretion and crustal thickening, has contributed to the crustal growth of the Philippine archipelago. 相似文献
149.
The use of geoprocessing to assess vulnerability on the east coast aquifers of Rio de Janeiro State,Brazil 总被引:1,自引:0,他引:1
Vinicius Silva Seabra Gerson Cardoso da SilvaJr Carla Bernadete Madureira Cruz 《Environmental Geology》2009,57(3):665-674
The east coast of Rio de Janeiro State, Brazil, shows a worrying overlap between areas with intrinsic groundwater vulnerability
and the most significant urban expansion zones. It experienced a rapid population growth in recent years, mainly due to the
tourism industry, resulting in a significant pressure on drinking groundwater resources. In this regard, development and use
of techniques to control and protect areas susceptible to contamination is crucial. The elaboration of aquifer vulnerability
maps is thus extremely helpful to support water resources management. The aim of the work is to present the methodological
approach in the use of Geoprocessing techniques to obtain a suitable groundwater vulnerability model in Rio de Janeiro east
coast. Considering the existing problems and the current land use and characteristics of the study region, it is clear that
the most vulnerable areas (that is, “extreme” and “very high” vulnerability areas), coincide with the most significant zones
of urban occupation, corresponding to 11% of the total study area, demanding adoption of urgent measures in the near future.
Geoprocessing tools and remote sensing for characterization of Rio de Janeiro’s east coast aquifer vulnerability gave good
results, representing a satisfactory method for management actions at low cost. 相似文献
150.
Luca Gasperini Enrico Bonatti Sonia Albertazzi Luisa Forlani Carla A. Accorsi Giuseppe Longo Mariangela Ravaioli Francesca Alvisi Alina Polonia Fabio Sacchetti 《地学学报》2009,21(6):489-494
Cheko, a small lake located in Siberia close to the epicentre of the 1908 Tunguska explosion, might fill a crater left by the impact of a fragment of a Cosmic Body. Sediment cores from the lake’s bottom were studied to support or reject this hypothesis. A 175‐cm long core, collected near the center of the lake, consists of an upper ~1 m thick sequence of lacustrine deposits overlaying coarser chaotic material. 210Pb and 137Cs indicate that the transition from lower to upper sequence occurred close to the time of the Tunguska Event. Pollen analysis reveals that remains of aquatic plants are abundant in the top post‐1908 sequence, but are absent in the lower pre‐1908 portion of the core. These results, including organic C, N and δ13C data, suggest that Lake Cheko formed at the time of the Tunguska Event. 相似文献