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181.
In 1830, Libri announced the finding of a 16-year-long record of daily temperature observed in Florence, Italy, by Father Renieri before the activity of the Medici Network (1654 to 1670) that is usually considered the earliest instrumental series in the world. The Libri announcement was supported by the concurrent finding of a box with the early Little Florentine Thermometers that survived the Inquisition and was confirmed by Schouw, von Humboldt and Maxwell. However, all investigations made to find Renieri’s observations were fruitless. This paper clarifies this complex situation differentiating between myth and reality. A careful analysis of the Libri’s announcement in the historical context points out that Libri made the announcement while escaping for conspiracy from Florence and needed a scoop to be introduced in the French Academy of Sciences. For this reason he made a deliberate mix of new and old assertions, i.e. he claimed to have made new discoveries but without explaining too much and reporting misleading details about well known stories concerning the earliest meteorological observations. This induced people to suppose that further, earlier records existed. The consequence of this was that climatologists searched for years the claimed records. This paper shows that the Medici Network almost certainly contains the earliest exploitable instrumental observations. The possibility of finding a short series of observations prior to 1654 is remote. 相似文献
182.
Diana Dell’Arciprete Chiara Vassena Fulvia Baratelli Mauro Giudici Riccardo Bersezio Fabrizio Felletti 《Hydrogeology Journal》2014,22(4):761-778
In porous aquifers, groundwater flow and solute transport strongly depend on the sedimentary facies distribution at fine scale, which determines the heterogeneity of the conductivity field; in particular, connected permeable sediments could form preferential flow paths. Therefore, properly defined statistics, e.g. total and intrinsic facies connectivity, should be correlated with transport features. In order to improve the assessment of the relevance of this relationship, some tests are conducted on two ensembles of equiprobable realizations, obtained with two different geostatistical simulation methods—sequential indicator simulation and multiple point simulation (MPS)—from the same dataset, which refers to an aquifer analogue of sediments deposited in a fluvial point-bar/channel association. The ensembles show different features; simulations with MPS are more structured and characterised by preferential flow paths. This is confirmed by the analysis of transport connectivities and by the interpretation of data from numerical experiments of conservative solute transport with single and dual domain models. The use of two ensembles permits (1) previous results obtained for single realizations to be consolidated on a more firm statistical basis and (2) the application of principal component analysis to assess which quantities are statistically the most relevant for the relationship between connectivity indicators and flow and transport properties. 相似文献
183.
This work examines the connection between Quaternary tectonics and erosion/incision processes in the primary Tuscan‐Romagna watershed of the Northern Apennines, which essentially coincides with the topographic culmination of the Nero Unit structural ridge. Tectonic and geomorphic information were collected in the area where this ridge is crossed by the upper Tiber River course forming a deep gorge. Structural analysis and field mapping have revealed that the region experienced polyphase tectonics with superposed thrust folding events identifiable both at the map and mesoscopic scales. Hinterland‐SSW‐verging thrusts and thrust‐related folds deformed the whole thrust pile during the latest deformation phase. Backthrusts/backfolds controlled the development of intermountain basins nearby the main watershed during the Early Pleistocene and seemingly deformed, in the Tiber gorge, a low‐relief landscape developed in the Early Pleistocene (ca. 1.1 Ma). Successively, the upper Tiber River course area and Apennines axial zone underwent a generalized uplift, which is manifested by the deep incision of palaeo‐morphologies. This proposed sequence of events correlates well with the major geodynamic change of the Apennines revealed by an acceleration of uplift rates in the Middle–Late Pleistocene. This latter event may also correlate with increased rates of river incision recorded in Europe as a consequence of uplift and/or climate change. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献