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81.
A study has been made of the time evolution of the flux of moisture E over grassland. The parameterization of E has been examined in order to formulate an equation depending on the net radiation flux and on bulk parameters which depend on the daily average meteorological situation and soil conditions. In particular the gradient of soil moisture has been recognized as playing a fundamental role in the time evolution of E(t). A time-dependent equation is proposed to compute in a statistical sense the irrigation needs or to forecast the hourly values of E(t), the maximum value E
0 and the time at which this maximum happens. 相似文献
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Elisabetta Tommasi Dario Lorenzetti Teresa Giannini Brunella Nisini Francesco Palla 《Astrophysics and Space Science》1998,261(1-4):187-190
We present far-infrared observations of the surroundings of the Herbig Be star LkHα234 in NGC7129, obtained with the Long
Wavelength Spectrometer on board of the Infrared Space Observatory. [CII]158μm, [OI]63μm and [OI]146μm lines are detected
everywhere in the mapped region and their intensity ratios are consistent with the model predictions of a photodissociation
region. The spatial distribution of the emission features indicates the presence of a peak which does not coincide with the
position of LkHα234, but is more likely associated with another nearby Herbig star, namely BD+65°1637; the far-ultraviolet
field intensity and the density derived from our observations are fully consistent with this hypothesis.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
84.
Mathematical Geosciences - Data assimilation methods are commonly used to predict petrophysical properties of deep saline aquifers for carbon dioxide sequestration studies. However, data... 相似文献
85.
de Figueiredo Leandro Passos Grana Dario Le Ravalec Mickaele 《Mathematical Geosciences》2020,52(6):801-816
Mathematical Geosciences - The fast Fourier transform-moving average (FFT-MA) is an efficient method for the generation of geostatistical simulations. The method relies on the calculation of a... 相似文献
86.
The Basilica of Santa Maria Maggiore, Rome, is an example of how ancient buildings with thick walls lessen the impact of the external temperature and humidity variations. The external influence on the internal microclimate is studied in order to gather information on how the building exchanges heat and moisture. Correlations between outdoor and indoor values are found. The results are applied to the calculation of the condensation-evaporation cycles inside micropores due to the Kelvin effect, to assess their impact on works of arts placed inside and outside the Basilica. It was found that the building attenuation is not sufficient to avoid damage due to condensation-evaporation cycles on stones and plasters. Some suggestions are made in order to mitigate the temperature variations during the liturgical offices. 相似文献
87.
Augusto Neri Paolo Papale Dario Del Seppia Roberto Santacroce 《Journal of Volcanology and Geothermal Research》2003,120(1-2):141-160
The AD 79 eruption of Vesuvius is certainly one of the most investigated explosive eruptions in the world. This makes it particularly suitable for the application of numerical models since we can be quite confident about input data, and the model predictions can be compared with field-based reconstruction of the eruption dynamics. Magma ascent along the volcanic conduit and the dispersal of pyroclasts in the atmosphere were simulated. The conduit and atmospheric domain were coupled through the flow conditions computed at the conduit exit. We simulated two different peak phases of the eruption which correspond to the emplacement of the white and gray magma types that produced Plinian fallout deposits with interlayered pyroclastic flow units during the gray phase. The input data, independently constrained and representative of each of the two eruptive phases, consist of liquid magma composition, crystal and water content, mass flow rate, and pressure–temperature–depth of the magma at the conduit entrance. A parametric study was performed on the less constrained variables such as microlite content of magma, pressure at the conduit entrance, and particle size representative of the eruptive mixture. Numerical results are substantially consistent with the reconstructed eruptive dynamics. In particular, the white eruption phase is found to lead to a fully buoyant eruption plume in all cases investigated, whereas the gray phase shows a more transitional character, i.e. the simultaneous production of a buoyant convective plume and pyroclastic surges, with a significant influence of the microlite content of magma in determining the partition of pyroclast mass between convective plumes and pyroclastic flows. 相似文献
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Statistical analyses on a catalogue of instrumental data for earthquakes in northeastern Italy since 1900 are presented. The different types of magnitude, which are the main parameters under study, have been evaluated so as to be as homogeneous as possible. Comparisons of the different magnitude values show linear dependence, at least in the medium magnitude range represented by the available data set. Correlations between the magnitude most significant for this region and chosen macroseismic data indicate a methodology for assessing the macroseismic magnitude of historical earthquakes which seems to be stable. 相似文献