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191.
The accelerated production and replacement of new electrical and electronic equipment demonstrates a tendency for the proportional increase in the generation of e‐waste. Developing countries experience similar social and environmental consequences from this trend, which compounds the other challenges associated with the already poor solid waste management in these regions. Moreover, the dangerous composition of some e‐waste amplifies the problems related to managing these materials. This mini‐review presents a brief overview of e‐waste management in Brazil, including technical aspects, scientific studies, and the challenges ahead. With the Brazilian National Policy of Solid Waste already in place, technical and scientific studies endorse measures that range from incorporating the informal recycling sector into the e‐waste management sector to encouraging the expansion of the recycling industry. All such actions, combined with an intensified commitment of electronic equipment manufacturers to reverse logistics, can improve e‐waste management in Brazil. 相似文献
192.
This article reviews the literature involving benthic invertebrates that are cited in association with hull fouling, reporting the species that occur on the Brazilian coast and evaluating the importance of this vector for the introduction of nonindigenous and cryptogenic invertebrates in Brazil. It discusses some of the strategies that were used by the species that allowed for their overseas transport and made it easier to cross natural barriers that otherwise would have been obstacles to their dispersion. The compiled data list 343 species (65% nonindigenous and 35% cryptogenic), mainly from the northwestern Atlantic Ocean. The traveling fauna, composed mostly of cosmopolitan species (70.3%), is primarily euryhaline and marine stenohaline, with sessile and sedentary habits. After delineating the shipborne species’ ecological profiles and traveling strategies and evaluating their overlapping vectors, we concluded that hull vessels were the main vector of introduction to the Brazilian coast for 89.8% of the compiled species. 相似文献
193.
Carlos A.F. Schettini Nils E. Asp Andrea S. Ogston Vando J.C. Gomes Robin L. McLachlan Marcus E.B. Fernandes Charles A. Nittrouer Eliane C. Truccolo Danilo C.L. Gardunho 《地球表面变化过程与地形》2020,45(3):574-589
The Amazon Macrotidal Mangrove Coast (AMMC) is a large (~7500 km2) contiguous mangrove fringe eastwards from the Amazon River mouth. It encompasses dozens of interconnected bays intercalated with mangrove peninsulas. Mud accumulates on the mangrove flats, whereas the bed of the bays and channels is generally sandy. In this study we investigated the circulation, sediment transport and deposition in a central site at one of these mangrove peninsulas. The study was undertaken during the dry period, when there is no influence of the Amazon River plume and minimum local freshwater inflow. Current and suspended-sediment concentration were monitored in a feeder channel on the mangrove flat along a ~1000 m section oriented along the peninsula axis. Sediment deposition was also measured on the flat. Our results show there was a strong exchange between the neighboring bays. Channel currents were flood dominant, reaching up to >1 m s−1, with residual water and sediment transport westwards. Suspended sediment concentration (SSC) in the channel was directly related to velocity magnitude, ranging between 50 and 350 mg L−1. The flat was flooded in a way that indicated the tidal wave evolves westwards, nearly parallel to the AMMC shoreline. Currents on the flats were much slower than those in the channel and showed slight ebb dominance. However, SSC was higher during the flood than ebb, clearly indicating settling during the current deceleration and limited erosion during the following ebb–flow acceleration. The net sediment transport across the section was 60 tons westwards for the period of the experiment (~4 days). The mean deposition rate was 0.006 kg m−2 s−1 (or 1.4 kg m−2 per tide), which was higher than rates from other reported assessments in mangroves. The set of results indicate very large internal sediment reworking in the AMMC. © 2019 John Wiley & Sons, Ltd. 相似文献
194.
Pereira Rodrigo Moura Bufon Vinícius Bof Maia Felipe Cardoso Oliveira 《Theoretical and Applied Climatology》2022,148(3-4):1249-1260
Theoretical and Applied Climatology - Gridded precipitation products from remote sensing are currently available and could potentially enhance the use of precipitation data in regions with sparse... 相似文献
195.
Silva Karita Almeida de Souza Rolim Glauco de Oliveira Aparecido Lucas Eduardo 《Theoretical and Applied Climatology》2022,148(3-4):1279-1288
Theoretical and Applied Climatology - The El Niño-Southern Oscillation (ENSO) phenomenon affects the global climate by changing temperature and precipitation patterns mainly in tropical... 相似文献
196.
Herrera Duvan Ricardo Herrera de Castro David Lopes Oliveira Jefferson Tavares Cruz de Oliveira Digenes Custdio 《Surveys in Geophysics》2022,43(3):883-912
Surveys in Geophysics - In this work, we calculated the Curie Point Depth (CPD) for the Brazilian Equatorial Margin using the Fourier and continuous wavelet (CWT) transforms considering a linear... 相似文献
197.
Strategies of Bioremediation for the Degradation of Petroleum Hydrocarbons in the Presence of Metals in Mangrove Simulated 下载免费PDF全文
198.
Kátia Martinello James C.Hower Diana Pinto Carlos E.Schnorr Guilherme L.Dotto Marcos Leandro Silva Oliveira Claudete G.Ramos 《地学前缘(英文版)》2022,(1):488-497
The ceramics industry,resulting from developments of modern compounds,is a segment of great influence in worldwide sustainability.Artisanal ceramic factories based on wood combustion have significant risks for the creation and discharge of atmosphere nanoparticles(NPs)and ultra-fine particles(UFPs).At present,there is insufficient recognition on the influence of engineered-NPs on the atmosphere and health.Real improvements are indispensable to diminish contact with NPs.The present study demonstrates the main NPs and UFPS present in an area of intense artisanal wood-combustion ceramic manufacturing.Particulate matter was sampled for morphological,chemical,and geochemical studies by sophisticated electron microbeam microscopy,X-Ray Diffraction,and Raman spectroscopy.From NPs configuration(<10 nm)we identify nucleation.Several amorphous NPs(>10 nm)were produced around the studied artisanal ceramic factories.This study presents an indication of the recent information on population and work-related contact to NPs in the artisanal ceramic factories and their influence on health. 相似文献
199.
Aracy Mendes da Costa Margarete Oliveira Domingues Odim Mendes Christiano Garnett Marques Brum 《Journal of Atmospheric and Solar》2011,73(11-12):1478-1491
One way to investigate the magnetosphere–ionosphere coupling is through the simultaneous observation of different parameters measured at different locations of the geospace environment and try to determine some relationships among them. The main objective of this work is to examine how the solar energetic particles and the interplanetary medium conditions may affect the space and time configuration of the ring current at low-latitudes and also to get a better understanding on how these particles interfere with the lower ionosphere in the South Atlantic Magnetic Anomaly region (SAMA). To accomplish this, the cosmic noise absorption (CNA) and the horizontal component of the Earth's magnetic field data measured from sites located in the SAMA region were compared with the proton and electron fluxes, interplanetary medium conditions (solar wind and the north–south component of the interplanetary magnetic field measured on board satellites), the SYM-H index and magnetometer data from Kakioka (KAK-Japan), located significantly outside the SAMA region. The time series analyzed correspond to the geomagnetic disturbance that occurred on August 25–30, 1998. The analysis was performed by implementing wavelet techniques, with particular attention to singularities detection, which highlights the presence of transient signals. The results are discussed in terms of the first three wavelet decomposition levels of the parameters. The magnitude of wavelet coefficients of the solar wind and proton flux at the two energy ranges analyzed is timely well correlated, indicating that these two signals are energetically linked. The larger wavelet coefficient amplitude of KAK and VSS magnetograms shows time delays that are compatible with an asymmetric configuration of the ring current, considering that at the storm time, VSS was at the dawn sector of the magnetosphere and KAK at the dusk side. The wavelet analysis of CNA signals reveals that the signal may be sensitive to the ionization produced by energetic electrons and protons as well. The time delays observed in wavelet coefficients may give an indication of the different accelerating process to which the particles are submitted when traveling along the magnetic field lines, from higher to lower latitudes, and the likely contribution of these particles to the ionization measured as an absorption of the cosmic noise in the lower ionosphere. 相似文献
200.
Sandra Plecha Paulo A. Silva Nuno Vaz Xavier Bertin Anabela Oliveira André B. Fortunato João M. Dias 《Ocean Dynamics》2010,60(2):275-284
This work investigates the recent morphological changes at the inlet of a complex coastal system (Ria de Aveiro lagoon, Portugal). This study was carried out using bathymetric data analysis and numerical simulations obtained with the
2DH morphodynamic modelling system MORSYS2D. The present simulations considered only tidal forcing, and a sensitivity analysis
was performed by tuning the formula used to compute the sediment transports. A non-uniform sediment grain size distribution
for the Ria de Aveiro inlet is considered in the numerical simulations, based on surveys performed in this area. The model results are analysed
to assess if they resemble the observed trends of erosion and deposition, as calculated from bathymetric data. A quantitative
analysis of the differences between the bathymetric changes obtained through surveys and the numerical results over a period
of 3 years considering different sediment transport formulations shows that the formulations of Ackers and White (1973) and Engelund and Hansen (1967) are the ones that best describe the morphodynamic changes driven by tides in the Ria de Aveiro inlet. 相似文献