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91.
OpenStreetMap (OSM) is an online public access database that allows for the collaborative collection of local geographic information. We employ this mapping technology to discuss a new social theory of poverty that moves away from income poverty to an economy that directly produces individuals' basic needs. Focusing on urban farming in Philadelphia as an example, we use OSM to support the argument that money, land, labor, and capital do not limit food production in the city. OSM is a type of “commons” that allows community members to depict features of interest to them that might otherwise be underrepresented in official or commercially produced maps such as Google Maps. Using the concept of facilitated volunteered geographic information (VGI) we developed an open framework for combining residents' local knowledge of food resources with expert guidance in data input. We believe this helps overcome problems with ad hoc data submission efforts to which collaborative online projects are susceptible. The program for “tagging” food resources in OSM was deployed in a public “map-a-thon” event we organized in Philadelphia, bringing together technical experts and food enthusiasts. To share the results, we present the Philly Fresh Food Map as an interactive online Web map that can be used and updated by the public. 相似文献
92.
Andrew J. Rettig Sumit Khanna Richard A. Beck Quinn Wojcik Carmen A. McCane 《International Journal of Digital Earth》2016,9(1):30-46
Sensor networks are an essential tool for environmental scientists. As scientists and engineers are beginning to utilize these new methods and devices in their fieldwork, they need to be actively involved in the future of sensor-networking development. Continued sensor network innovation is important for improved standardization, affordability, and interoperability. This article uses a storm water case study to outline an end-to-end open-innovation sensor network. Open innovation by scientists, engineers, and entities is the collaborative process of creating value for this project in permeable paver runoff data and advances within sensor networking. This article focuses on the technical implementation of the near–real-time location and temporally aware sensor network. Data are streamed in near–real-time with subliter precision to the cloud using common off-the-shelf routers. The sensors use Maxim's 1-wire? protocol, and the unique digital serial numbers confirm the data. The data retrieved compare residence times within the permeable paver catchment basins and the control basin. Sensor network advances are made by bridging the gap between sensor protocols and communication systems. These advances enable the development of open-source representational state transfer web services. Our successful implementation serves as an example for others to study and expand upon for a variety of monitoring solutions. 相似文献
93.
94.
An understanding of the hydraulic properties of the aquifer and the depth distribution of salts is critical for evaluating the potential of ground water for conjunctive water use and for maintaining suitable ground water quality in agricultural regions where ground water is used extensively for irrigation and drinking water. The electrical conductivity profiles recorded in a well using the flowing fluid electric conductivity (FEC) logging method can be analyzed to estimate interval-specific hydraulic conductivity and estimates of the salinity concentration with depth. However, operating irrigation wells commonly allow limited access, and the traditional equipment used for FEC logging cannot fit through the small access pipe intersecting the well. A modified, miniaturized FEC logging technique was developed for use in wells with limited access. In addition, a new method for injecting water over the entire screened interval of the well reduces the time required to perform FEC logging. 相似文献
95.
Paul F. Schofield Andrew D. Smith J. Frederick W. Mosselmans Hendrik Ohldag Andreas Scholl Simone Raoux Gordon Cressey Barbara A. Cressey Paul D. Quinn Caroline A. Kirk Simon C. Hogg 《Geostandards and Geoanalytical Research》2010,34(2):145-159
This work describes the application of microfocus X-ray absorption spectroscopy (XAS) and X-ray photo-emission electron microscopy (XPEEM) to the study of the complex mineralogical intergrowths within the Santa Catharina meteorite. The Santa Catharina meteorite of this study (BM52283 from the meteorite collection of the Natural History Museum, London, UK) primarily comprises a taenite bulk host phase (Fe:Ni ratio = 70.9 ± 0.8%:29.1 ± 0.8%) with a set of oxide-bearing cloudy zone textured regions (Fe:Ni:O ratio = 40.4 ± 0.3%:49.0 ± 0.7%:10.6 ± 0.8% at the core and Fe:Ni:O ratio = 34.4 ± 1.5%:42.7 ± 0.6%:22.9 ± 1.8% towards the rims) and numerous schreibersite (Fe:Ni:P ratio = 38.6 ± 1.6%:38.4 ± 0.9%:23.0 ± 0.5%) inclusions. Between the schreibersite and the taenite are rims up to 50 μm across of Ni-rich kamacite (Fe:Ni ratio = 93.4 ± 0.4%:6.6 ± 0.5%). No chemical zoning or spatial variations in the Fe and Ni speciation was observed within either the schreibersite or the kamacite phases. The oxide-bearing cloudy zone textured regions mostly comprise metallic Fe–Ni alloy, predominantly tetrataenite. Within the oxide phases, the Fe is predominantly, but not entirely, tetrahedrally co-ordinated Fe3+ and the Ni is octahedrally co-ordinated Ni2+. Structural analysis supports the suggestion that non-stoichiometric Fe2NiO4 trevorite is the oxide phase. The trevorite:tetrataenite ratio increases at the edges of the oxide-bearing cloudy zone textured regions indicating increased oxidation at the edges of these zones. The spatial resolution of the XPEEM achieved was between 110 and 150 nm, which precluded the study of either the previously reported ∼ 10 nm precipitates of tetrataenite within the bulk taenite or any antitaenite. 相似文献
96.
97.
Robert Wood Doug Johnson Simon Osborne Meinrat O. Andreae Brain Bandy Timothy S. Bates Colin O'Dowd Paul Glantz Kevin Noone Patricia K. Quinn Jochen Rudolph Karsten Suhre 《Tellus. Series B, Chemical and physical meteorology》2000,52(2):401-422
Aircraft measurements are presented of the Lagrangian evolution of a marine boundary layer over a 30‐h period during the ACE‐2 field campaign. At the start of the observational period, a 500‐m deep polluted marine internal boundary layer (MIBL) was overlain by the remnants of a polluted continental boundary layer extending to around 2 km below a clean, dry free troposphere. The MIBL grew rapidly to a thickness of 900–1000 m in response to increasing sea surface temperatures. No significant aerosol spectral evolution was observed in the boundary layer. Low concentrations of SO2 were observed in the MIBL suggesting that the air mass contained relatively aged aerosol. Aerosol spectra show a broad mode with a modal diameter of around 0.1μm. The polluted layer between the MIBL and the unpolluted free troposphere was only weakly and intermittently turbulent which prevented significant entrainment of clean air into the polluted layer from aloft. The polluted layer depth was thus controlled mainly by subsidence which as a result becomes shallower, decreasing from over 2000 m to around 1200 m during the observational period. The aerosol characteristics of the polluted layer were similar to those in the MIBL and so although the MIBL entrained considerable amounts of air from above the MIBL the aerosol characteristics underwent no significant change. This has important implications for the rate at which a polluted continental air mass is converted to a clean marine one. The dataset should prove useful in the validation of the modelling of continental pollution outbreaks. 相似文献
98.
99.
We present results from 44 simulations of late stage planetary accretion, focusing on the delivery of volatiles (primarily water) to the terrestrial planets. Our simulations include both planetary “embryos” (defined as Moon to Mars sized protoplanets) and planetesimals, assuming that the embryos formed via oligarchic growth. We investigate volatile delivery as a function of Jupiter's mass, position and eccentricity, the position of the snow line, and the density (in solids) of the solar nebula. In all simulations, we form 1-4 terrestrial planets inside 2 AU, which vary in mass and volatile content. In 44 simulations we have formed 43 planets between 0.8 and 1.5 AU, including 11 “habitable” planets between 0.9 and 1.1 AU. These planets range from dry worlds to “water worlds” with 100+oceans of water (1 ocean=1.5×1024 g), and vary in mass between 0.23M⊕ and 3.85M⊕. There is a good deal of stochastic noise in these simulations, but the most important parameter is the planetesimal mass we choose, which reflects the surface density in solids past the snow line. A high density in this region results in the formation of a smaller number of terrestrial planets with larger masses and higher water content, as compared with planets which form in systems with lower densities. We find that an eccentric Jupiter produces drier terrestrial planets with higher eccentricities than a circular one. In cases with Jupiter at 7 AU, we form what we call “super embryos,” 1-2M⊕ protoplanets which can serve as the accretion seeds for 2+M⊕ planets with large water contents. 相似文献
100.
Quantification of uncertainty sources in a probabilistic climate change assessment of future water shortages 总被引:1,自引:0,他引:1
As the incorporation of probabilistic climate change information into UK water resource management gathers apace, understanding the relative scales of the uncertainty sources in projections of future water shortage metrics is necessary for the resultant information to be understood and used effectively. Utilising modified UKCP09 weather generator data and a multi-model approach, this paper represents a first attempt at extending an uncertainty assessment of future stream flows under forced climates to consider metrics of water shortage based on the triggering of reservoir control curves. It is found that the perturbed physics ensemble uncertainty, which describes climate model parameter error uncertainty, is the cause of a far greater proportion of both the overall flow and water shortage per year probability uncertainty than that caused by SRES emissions scenario choice in the 2080s. The methodology for producing metrics of future water shortage risk from UKCP09 weather generator information described here acts as the basis of a robustness analysis of the North Staffordshire WRZ to climate change, which provides an alternative approach for making decisions despite large uncertainties, which will follow. 相似文献