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81.
Konrad J. K. Büttner 《Theoretical and Applied Climatology》1958,9(1):80-85
Zusammenfassung Laboratoriumsversuche und Feldbeobachtungen zeigen einen unerwartet starken Transport von Wasserdampf in die menschliche Haut,
in getrocknete und in lebende Pflanzen und in trockenen Erdboden hinein. Diese Vorg?nge selbst beruhen offenbar auf Diffusion
und Sorption. Dabei ist für menschliche Haut und für Pflanzen das Entstehen hoher osmotischer Drucke, d. h. niederer Wasserkonzentration,
wahrscheinlich gemacht; doch sind die Ursachen dafür noch unbekannt.
Contribution Number 32 of the Department of Meteorology and Climatology, University of Washington.
Herrn Dr.Anders K. ?ngstr?m zu seinem 70. Geburtstag gewidmet. 相似文献
Summary Laboratory experiments and field observations show surprisingly high amounts of transfer of water vapor into human skin, into dry and living plants, and into dry soil. The processes involved seem to be based on diffusion and sorption. These results may be explained by assuming the existence of high osmotic pressures in skin and in plants; the reason for this concentration is not yet known.
Résumé Des essais de laboratoire et dans la nature montrent un transport inattendu de vapeur d'eau dans la peau humaine, dans des plantes séchées et vivantes ainsi que dans le sol sec. Les phénomènes reposent apparemment sur la diffusion et sur la sorption. En ce qui concerne la peau humaine et les plantes, il est donc probable qu'elles entretiennent des pressions osmotiques élevées; mais la cause en est encore inconnue.
Contribution Number 32 of the Department of Meteorology and Climatology, University of Washington.
Herrn Dr.Anders K. ?ngstr?m zu seinem 70. Geburtstag gewidmet. 相似文献
82.
83.
Prof. Dr. J. K. Von Baars Frau Dr. Ivonne J. le Cosquino de Bussy 《Aquatic Sciences - Research Across Boundaries》1960,22(1):380-395
Ohne Zusammenfassung 相似文献
84.
85.
Konrad J. KossackiWojciech J. Markiewicz 《Icarus》2002,160(1):73-85
The Mars Orbiter Camera onboard the Mars Global Surveyor has obtained several images of polygonal features in the southern polar region. In images taken during the end of the southern spring, when the surrounding surface is free of the seasonal frost, CO2 ice still appears to be present within the polygonal troughs. In Earth's polar regions, polygons such as these are indicative of water ice in the ground below. We analyzed the seasonal evolution of the thermal state and the CO2 content of these features. Our 2-D model includes condensation and sublimation of the CO2 ice, a self consistent treatment of the variations of the thermal properties of the regolith, and the seasonal variations of the local atmospheric pressure which we take from the results of a general circulation model. We find that the residence time of seasonal CO2 ice in troughs depends not only on atmospheric opacity and albedo of the CO2 ice, but also and most significantly on the distribution of water ice in the regolith. Optical properties of the atmosphere and surface CO2 ice can be independently obtained from observations. To date this is not true about the distribution of water ice below the surface. Our analysis quantifies the dependence of the seasonal cycle of the CO2 ice within the troughs on the assumed distribution of the water ice below the surface. We show that presence of water ice in the ground at a depth smaller than the depth of the troughs reduces winter condensation rate of CO2 ice. This is due to higher heat flux conducted from the water ice rich regolith toward the facets of the troughs. 相似文献
86.
C. E. Konrad 《Theoretical and Applied Climatology》1998,60(1-4):11-19
Summary Previous work has examined relationships between the planetary scale Pacific North American (PNA) teleconnection pattern
and regional scale mean temperature over portions of the United States, but analyses have been restricted to monthly values
of these two variables. It is not clear if this is the most appropriate scale for relating PNA patterns to temperature. In
this study, PNA indices are related to various aspects of temperature over a range of time scales spanning one month. To carry
this out, standardized PNA indices are calculated for 6 time intervals ranging from 5 to 30 days over a period of 27 winter
seasons. Standardized regional scale temperature anomalies are assessed over various regions of the United States and used
to compute mean, maximum, and minimum temperature anomalies over the same 6 time intervals. Correlation matrices are then
constructed to provide relationship characteristics between the PNA indices and temperature measures within the intramonthly
time scale.
Only the southeastern and northwestern regions of the United States display significant relationships between the PNA indices
and temperature. Over the Southeast, temperature anomalies on short time scales relate most strongly to PNA indices computed
over time intervals of 25 to 30 days; this is especially the case for the minimum temperature anomaly. The strongest relationships,
however, are observed between the PNA index and temperature anomalies computed on a 20–25 day time interval. Over the Northwest,
the relationships are not as strong and somewhat more varied. Most notably, moderate connections are found between the 30
day PNA index and minimum temperature anomalies computed over a 25 day period.
Received August 18, 1997Revised November 28, 1997 相似文献
87.
A Servohydraulically-controlled Deformation Apparatus for Rock Deformation under Conditions of Ultra-high Pressure Metamorphism 总被引:5,自引:0,他引:5
E. Rybacki J. Renner K. Konrad W. Harbott F. Rummel B. Stöckhert 《Pure and Applied Geophysics》1998,152(3):579-606
—A deformation apparatus has been developed to study the mechanical behaviour of high pressure and ultra-high pressure metamorphic rocks. It is based on the conventional Griggs design and the molten salt cell concept introduced by H. E. Green II. Both, the axial loading and the confining pressure are servohydraulically controlled. Alternatively, a self-made multilayer pressure vessel or a commercial stripwound construction are used. The pressure cell is improved with respect to systems described previously by the use of different salt mixtures with low eutectic temperatures, by a mechanically stable arrangement of the thermocouples, and by an optimization of the frictional characteristics of the axial loading system. The apparatus has been successfully used in deformation experiments on cylindrical aragonite and coesite samples 3 to 4 mm in diameter and 6 to 10 mm in length at confining pressures up to 3.7 GPa and temperatures up to 1170°C. 相似文献
88.
Michael R. Merrifield & Konrad Kuijken 《Monthly notices of the Royal Astronomical Society》1998,297(4):1292-1296
We show that the kinematics of the shells seen around some elliptical galaxies provide a new, independent means for measuring the gravitational potentials of elliptical galaxies out to large radii. A numerical simulation of a set of shells formed in the merger between an elliptical and a smaller galaxy reveals that the shells have a characteristic observable kinematic structure, with the maximum line-of-sight velocity increasing linearly as one moves inward from a shell edge. A simple analytic calculation shows that this structure provides a direct measure of the gradient of the gravitational potential at the shell radius. In order to extract this information from attainable data, we have also derived a complete distribution of line-of-sight velocities for material within a shell; comparing the observed spectra of a shell to a stellar template convolved with this distribution will enable us to measure the gradient of the potential at this radius. Repeating the analysis for a whole series of nested shells in a galaxy allows the complete form of the gravitational potential as a function of radius to be mapped out. The requisite observations lie within reach of the up-coming generation of large telescopes. 相似文献
89.
Malherbe J. M. Schmieder B. Mein P. Mein N. Van Drielgesztelyi L. Von Uexküll M. 《Solar physics》1998,180(1-2):265-284
Using multi-wavelength observations obtained with the Tenerife telescopes (VTT and GCT) and with the Yohkoh satellite, we observed new emerging flux with an associated arch filament system (AFS) in the chromosphere and bright X-ray loops in the corona. We observed the change of connectivity of the X-ray loop footpoints which may be at the origin of the occurrence of a subflare. Densities, gas and magnetic pressures of cold AFS and hot loops were derived and discussed. The extrapolation of the photospheric magnetic field observed with the GCT in a linear force-free field assumption (constant ) shows that this region, in spite of having roughly a global potential configuration, consists of two systems of arch filaments. We found these two systems best fitted with two sheared magnetic topologies of opposite values of ± 0.1 Mm-1 相似文献
90.
The ramifications of a particular type of causality constraint, namely so-called shadow-zones, are explored in the context of time-dependent boundary element methods. In particular, wave propagation problems in 2-D elastic soil media with a non-convex shape are analysed. 相似文献