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111.
Daily meteorological observations have been made at the Brera astronomical observatory in Milan since 1763. Initially they concerned air temperature, air pressure, wind direction and state of the sky; other measurements such as precipitation, relative humidity and wind speed were gradually included in the following years. In terms of homogeneity the series can be divided into two main periods, due to the great reorganisation of the observations that Francesco Carlini performed in 1835. As a consequence of other minor changes, each of these periods can then be divided into some other sub-periods, the most problematic years being the first (1763–1804) and the last (1963–today) ones. Within this context the purpose of the paperis to present the history of Milan's temperature and pressure series, giving particular emphasis to all the information that can be useful for the evaluation of the reliability and of the homogeneity of the data. Moreover the data recovery is discussed and the quality and the availability of both hand-written (observatory registers) and published (ephemeridis, bulletins, year-books) data and metadata sources are analysed. 相似文献
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Rodolfo Carosi Chiara Montomoli Nicola Bertuccelli Maurizio Profeti 《Comptes Rendus Geoscience》2002,334(5):339-346
Structural analysis performed in the southern sector of the Apuan Alps Metamorphic Complex (AAMC) and on the overlaying Tuscan Nappe (TN) pointed out a structural evolution much more complex than that outlined till now. The comparison between the structural evolutions of the two tectonic units could provide new important constraints on the tectonic evolution of the whole belt. The two tectonic units recorded different tectonic evolution during the first stages of compression, while they shared the same deformation history later after the Tuscan Nappe overlapped the AAMC. The coupled tectonic units have been then deformed by two systems of folds, in a compressive tectonic regime. Extensional tectonics affected the units later, at upper crustal levels. To cite this article: R. Carosi et al., C. R. Geoscience 334 (2002) 339–346. 相似文献
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Zeolitization of Oligo-Miocene volcaniclastic rocks from Logudoro (northern Sardinia, Italy) 总被引:1,自引:0,他引:1
Guido Cerri Piergiulio Cappelletti Alessio Langella Maurizio de'Gennaro 《Contributions to Mineralogy and Petrology》2001,140(4):404-421
The present study reports the results of research on volcaniclastic products from Logudoro (northern Sardinia), a reconstructed
stratigraphic succession some hundreds of meters thick, comprising two different ignimbritic units separated by an epiclastic
layer (generally ˜10 m thick). Clinoptilolite is the most widely distributed authigenic phase in epiclastite and unwelded
units, always associated with opal-CT and sometimes with smectite. An adularia-like feldspar, cristobalite and epigenetic
quartz are typical phases of welded units. Within the zeolitized units (unwelded ignimbrite and epiclastic units) clinoptilolite
and opal-CT constitute the cement deriving from the transformation of the precursor rhyolitic glass, in agreement with a single
zeolitization process that developed after the deposition of the entire succession. Silica increases in zeolitized rocks with
respect to the precursor material, leading to hypothesize that the secondary mineralization process was favored by mineralized
hydrothermal fluids preferentially circulating through the fault system of the area. Quartz veins in welded subunit and K-feldspar
(adularia-like) preferentially located near the faults are in agreement with this hypothesis. The interaction of these fluids
with the glassy fraction favored its dissolution and the consequent crystallization of clinoptilolite. Furthermore, the pH
increase and the silica supersaturation enhanced the contemporary or subsequent precipitation of opal-CT.
Received: 5 June 2000 / Accepted: 14 August 2000 相似文献
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Maurizio De Rosa Gianluca Gagliardi Alessandra Rocco Renato Somma Paolo De Natale Giuseppe De Natale 《Geochemical transactions》2007,8(1):5
We report on a continuous-measurement campaign carried out in Vulcano (Aeolian islands, Sicily), devoted to the simultaneous
monitoring of CO2 and H2O concentrations. The measurements were performed with an absorption spectrometer based on a semiconductor laser source emitting
around a 2-μm wavelength. The emitted radiation was selectively absorbed by two molecular ro-vibrational transitions specific of the investigated
species. Data for CO2 and H2O concentrations, and CO2 soil diffusive flux using an accumulation chamber configuration, were collected at several interesting sampling points on
the island (Porto Levante beach- PLB, Fossa Grande Crater – FOG- and Valley of Palizzi, PAL). CO2/H2O values, measured on the ground, are very similar (around 0.019 (± 0.006)) and comparable to the previous discrete detected
values of 0.213 (Fumarole F5-La Fossa crater rim) and 0.012 (Fumarole VFS – Baia Levante beach) obtaid during the 1977–1993
heating phase of the crater fumaroles. 相似文献