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SUMMARY
A comparison is made between the void ratio and pressure relationships resulting from a laboratory consolidation test and a sedimentation-compression computation on a short core of calcareous mud or ooze of low plasticity. Geo-technical measurements of grain size, bulk density, Atterberg limits, water content, vane shear strength, pore-water salinity, and carbonate content are graphically related to depth in the core. Results of the laboratory consolidation test on this material differ markedly from the in-place relationship between void ratio, or water content, and the effective overburden pressure, or burial depth, shown by the sedimentation-compression curve. The previous maximum consolidation pressure, based on laboratory consolidation test data, is about 60 times greater than the computed in-place effective overburden pressure. An explanation for this difference would include the different magnitudes of time available for consolidation, cementation occurring in-place, and orientation of the constituents. It is suggested that results of the consolidation test on carbonate muds or oozes should be interpreted with caution for geological and engineering purposes. 相似文献
A comparison is made between the void ratio and pressure relationships resulting from a laboratory consolidation test and a sedimentation-compression computation on a short core of calcareous mud or ooze of low plasticity. Geo-technical measurements of grain size, bulk density, Atterberg limits, water content, vane shear strength, pore-water salinity, and carbonate content are graphically related to depth in the core. Results of the laboratory consolidation test on this material differ markedly from the in-place relationship between void ratio, or water content, and the effective overburden pressure, or burial depth, shown by the sedimentation-compression curve. The previous maximum consolidation pressure, based on laboratory consolidation test data, is about 60 times greater than the computed in-place effective overburden pressure. An explanation for this difference would include the different magnitudes of time available for consolidation, cementation occurring in-place, and orientation of the constituents. It is suggested that results of the consolidation test on carbonate muds or oozes should be interpreted with caution for geological and engineering purposes. 相似文献
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Walter E. Brown Jr. 《Earth, Moon, and Planets》1972,4(1-2):113-127
The Apollo Lunar Sounder Experiment that is scheduled to orbit the Moon on Apollo 17 consists of a three frequency coherent radar system and an optical recorder. The coherent radar can be used to measure both phase and amplitude characteristics of the radar echo. Measurement methods that are related to the phase and amplitude will be used to determine the surface profile, locate subsurface features and ascertain near surface electrical properties of the lunar surface. The key to the coherent radar measurement is a highly stable oscillator that preserves an accurate phase reference (2 or 3 electrical degrees) over a long period of time. This reference provides a means for reducing surface clutter so that subsurface features are more easily detected and also provides a means of measuring range to the surface to within a fraction of a wavelength. 相似文献
997.
Upper and lower limits on the physical parameters for Cen X-3 and Her X-1 have been computed from a simple assumption involving the mass function. 相似文献
998.
999.
William Henze Jr. 《Solar physics》1969,9(1):65-76
Slitless spectrograms of the chromosphere obtained during the eclipse of 4–5 February 1962 have been analyzed to obtain the decrements of the level populations of hydrogen, the self-absorption in the Balmer lines, and parameters useful in construction of models of the low chromosphere.The decrement of the high energy levels of hydrogen inferred under the optically thin assumption does not vary significantly with height, and it appears to be unnecessary to seek large deviations from local thermodynamic equilibrium in the high levels. The observed Balmer-to-Paschen line intensity ratios have been used to infer self-absorption and opacities in the Balmer lines. The resulting population of the second energy level is about an order of magnitude smaller than that found by Athay and Thomas from the 1952 data.The chromospheric continuum was generally underexposed; the absence of observed continuum in the visible region of the spectrum made it impossible to derive a unique model from the 1962 data alone. However, the high Balmer line data and new theoretical solutions of the statistical equilibrium equations for hydrogen combined with corrected 1952 observations at 4700 A are compatible with a model having approximately the same temperature and neutral hydrogen structure as the 1952 model by Pottasch and Thomas but half the electron density: T
e = 6200K, N
1 = 7.4 × 1013 cm-3, N
e = 2.3 × 1011 cm-3 at 500 km and T
e = 7200K, N
1 = 2.6 × 1012 cm-3, N
e = 1.7 × 1011 cm-3 at 1000 km.Based in part on a Ph.D. thesis submitted to the Department of Astro-Geophysics, University of Colorado.Now at the Department of Astronomy, Indiana University. 相似文献
1000.