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101.
Mineral particles could have influenced on the climate of Oviedo, a non-industrial city situated in the centre of an industrial
zone of the North of Spain, increasing the temperature and the precipitations, in spite of the fact that “greenhouse gases”
concentrations have diminished in this city in recent years. The directive (1999/30/EC) of the European Commission began to
be applied in Oviedo in the year 2003. In agreement with this norm, our first aim was the identification of the inorganic
particulate matter of the PM10 and PM2.5 fractions sampled in this city. X-ray diffraction and scanning electron microscopy
coupled with X-ray dispersive energy spectrometry were used. The percentages of the different mineral phases of the PM were
obtained by a Rietveld refinement of powder X-ray diffraction data. The compositions of the PM10 and PM2.5 fractions of this
city are similar. Sulphates are the most abundant particles in the both fractions. Most sulphates, nitrates and sal-ammoniac
would have formed by reaction between solid, liquid and/or gas particles and they could be associated with the power stations
near to the city and traffic. Wüstite and haematites come from the iron and steel industries of Gijón and Avilés. The main
natural sources of halite and carbonates and silicates are sea spray and soil resuspension by the wind, respectively. 相似文献
102.
103.
Marcos A. E. Chaparro Juan M. Lirio Héctor Nuñez Claudia S. G. Gogorza Ana M. Sinito 《Environmental Geology》2005,49(1):30-43
Magnetic properties of lagoon and stream sediments from Chascomús area (Buenos Aires Province) and the relevance of various magnetic parameters as giving pollution status are studied in the present work. This work is focussed on magnetic parameters, such as concentration-dependent (magnetic susceptibility, saturation anhysteric and isothermal remanent magnetisation) and feature-dependent parameters (S-ratio, coercivity of remanence, anhysteric susceptibility/magnetic susceptibility-ratio), as pollution indicators. Firstly and most importantly, different magnetic parameters and chemical measurements were correlated in order to investigate their goodness, obtaining the best results for feature-dependent magnetic parameters. Coercivity of remanence correlate very well with chemical variables, showing correlations at high level of significance up to 0.9094, and the anhysteric susceptibility/magnetic susceptibility-ratio also shows very good correlations (up to 0.8376). Some results and advantages of using a new experimental method in order to discriminate hard and soft magnetic phases are also shown. This method uses alternately backfield isothermal remanent magnetisation and alternating field demagnetisation. From the experimental separation, the presence of hard magnetic phases in some samples was confirmed. 相似文献
104.
The structural analysis of regional 3D seismic data shows evidence of long-term tectonic inheritance in Campos Basin, offshore Brazil. Main Lower Cretaceous rift structures controlled themselves by strike-slip deformation belts related to Proterozoic orogenic events, have been episodically reactivated during the divergent margin phase of Campos Basin, from the Albian to the Miocene. Balanced cross-sections of major salt structures indicate that such tectonic reactivations have been controlling thin-skinned salt tectonics, triggering pulses of gravitational gliding above the Aptian salt detachment. Additionally, major basin features like the Neogene progradation front and the salt tectonic domains are constrained by the main Proterozoic orogenic trends of the Ribeira Belt (NE–SW) and the Vitória-Colatina Belt (NNW–SSE). As the basement involved structures observed in Campos Basin can be attributed to general geodynamic processes, it is suggested that basement tectonic reactivation can be as relevant as isostatic adjustment and detached thin-skinned tectonics on the structural evolution of divergent margin settings. 相似文献
105.
Dr. Alberto Marcos Dr. Maria L. Arboleya 《International Journal of Earth Sciences》1975,64(1):278-287
Examples of progressive deformation provided by minor structures are not frequent in the geological literature. In NW Spain some minor structures in Lower Paleozoic inhomogeneous layered material may be interpreted as the result of progressive deformation during the Hercynian Orogeny. The examples described include structures generated by progressive contraction (folded wedges), contraction followed by elongation (folds disrupted by boudinage) and elongation followed by contraction (folded boudins). 相似文献
106.
Paulo Marcos Daniel A.Gregori Leonardo Benedini Mercedes Barros Leonardo Strazzere Cecilia Pavon Pivetta 《地学前缘(英文版)》2018,9(2):485-504
The metasedimentary sequence of the Cushamen Formation in the western North Patagonian Massif is540 m thick and comprises six sedimentary lithofacies associations related to a glacimarine environment.Four of these lithofacies represent distal glacimarine environments, whereas another one was deposited in proximal glacimarine environments, and the last includes subglacial environments. The organization and configuration of these lithofacies associations represent the advance and retreat of the glacier masses. The maximum glacial advance is correlatable with the G2 glacial interval of the Pennsylvanian Pampa de Tepuel, Las Salinas and Valley Chico, formations of the Extraandean Chubut, and the southern part of Neuquen Cordillera. Contemporaneously, in southern Chile there are marine and glacimarine sediments. The chronostratigraphic relationships between the Silurian to Permian units allow five paleogeographic stages to be distinguished. The middle Silurian-late Devonian igneous rocks represent the first magmatic stage. The second stage, which is transitional to the first, is represented by a marine basin that includes the late Devonian-early Carboniferous Esquel and Rio Pescado formations and the Llanquihue Complex. The third stage(early-late Carboniferous) includes granitoids of the second magmatic event that partially overlapped the first magmatic igneous belt. The fourth stage belongs to the late Carboniferous sedimentation of the Cushamen and equivalent formations. The extended early Permian magmatism was the last Paleozoic event in the studied area. 相似文献
107.
Guillem Chust Ainhoa Caballero Marta Marcos Pedro Liria Carlos Hernández Ángel Borja 《Estuarine, Coastal and Shelf Science》2010
Global climate models have predicted a rise on mean sea level of between 0.18 m and 0.59 m by the end of the 21st Century, with high regional variability. The objectives of this study are to estimate sea level changes in the Bay of Biscay during this century, and to assess the impacts of any change on Basque coastal habitats and infrastructures. Hence, ocean temperature projections for three climate scenarios, provided by several atmosphere–ocean coupled general climate models, have been extracted for the Bay of Biscay; these are used to estimate thermosteric sea level variations. The results show that, from 2001 to 2099, sea level within the Bay of Biscay will increase by between 28.5 and 48.7 cm, as a result of regional thermal expansion and global ice-melting, under scenarios A1B and A2 of the Intergovernmental Panel on Climate Change. A high-resolution digital terrain model, extracted from LiDAR, data was used to evaluate the potential impact of the estimated sea level rise to 9 coastal and estuarine habitats: sandy beaches and muds, vegetated dunes, shingle beaches, sea cliffs and supralittoral rock, wetlands and saltmarshes, terrestrial habitats, artificial land, piers, and water surfaces. The projected sea level rise of 48.7 cm was added to the high tide level of the coast studied, to generate a flood risk map of the coastal and estuarine areas. The results indicate that 110.8 ha of the supralittoral area will be affected by the end of the 21st Century; these are concentrated within the estuaries, with terrestrial and artificial habitats being the most affected. Sandy beaches are expected to undergo mean shoreline retreats of between 25% and 40%, of their width. The risk assessment of the areas and habitats that will be affected, as a consequence of the sea level rise, is potentially useful for local management to adopt adaptation measures to global climate change. 相似文献
108.
Cataclysmic Variables (CVs) are close binary systems where mass is transferred from a red dwarf star to a white dwarf star via an accretion disk. The flickering is observed as stochastic variations in the emitted radiation both in the continuum and in the emission line profiles.The main goal of our simulations is to compare synthetic Doppler maps with observed ones, aiming to constrain the flickering properties and wind parameters.A code was developed which generates synthetic emission line profiles of a geometrically thin and optically thick accretion disk. The simulation allows us to include flares in a particular disk region. The emission line flares may be integrated over arbitrary ‘`exposure’' times, producing the synthetic line profiles. Flickering Doppler maps are created using such synthetic time series. The presence of a wind inside the Roche lobe was also implemented. Radiative transfer effects in the lines where taken into account in order to reproduce the single peaked line profiles frequently seen in nova-like CVs. 相似文献
109.
110.
Alexander Meneses Walter Vergara Keisuke Hanaki Mickiel Doorn Eudes Hernández Marcos Gryshek Alfred Grunwaldt Alejandro Deeb 《洁净——土壤、空气、水》2008,36(9):788-797
Greenhouse gas emissions from the waste sector account for only 4% of the total production, with wastewater management accounting for accurately 8 to 10% of this contribution. Wastewater disposal and treatment activities, mainly contributes to non‐CO2 gases such as methane (CH4) and nitrous oxide (N2O). Capturing or avoiding these emissions is thus both a concern and an opportunity. The clean development mechanism (CDM) offers an instrument to internalize global climate concerns into the design of wastewater treatment facilities. Properly designed facilities could improve effluent quality and optimize the abatement of greenhouse gas emissions, thus ensuring additional revenues to pay for capital, operation and maintenance costs and possibly justify higher levels of wastewater treatment. This document summarizes the experience of the “Rio Frio CDM project” in Colombia, as an example of what is achievable through the CDM application in wastewater treatment upgrade in developing countries. This document summarizes the scope of the project, the methodology used to establish current greenhouse emissions and future reductions, and the estimated financial results. 相似文献