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21.
Olaf Brockamp Evaristo Goulart Hermann Harder Annerose Heydemann 《Contributions to Mineralogy and Petrology》1978,68(1):85-88
Detailed studies on the copper and zinc distribution in metalliferous sediments from the Atlantis II Deep (Red Sea) demonstrate that beside chalcopyrite and sphalerite appreciable amounts of copper and zinc are found in X-ray amorphous copper and zinc sulfides not previously described. Only low contents of copper and zinc are present in nontronites, hydroxides and carbonates. 相似文献
22.
Hermann Korn 《International Journal of Earth Sciences》1956,45(2):337-341
Ohne Zusammenfassung 相似文献
23.
Hermann Gucinski 《Estuaries and Coasts》1978,1(3):151-156
Marshes located on the Mayo Peninsula between the South and Rhode rivers, Maryland, were measured to determine acreage per tract, total upland and seaward edge lengths. For these marshes, 54% of the total area is associated with tracts of less than 5 acres. Of total upland edge length, 68% is along tracts less than 5 acres, while 72% of seaward edge length is associated with these smaller tracts. Comparison of edge length to area ratios shows that tracts of 1 acre or less have significantly higher edge length than tracts of 5 acres or more. While this should be extrapolated to other geographic regions with care, the findings suggest that regulatory agencies revise wetland management principles to include greater protection and enhanced survival of small tracts. 相似文献
24.
Reviewing the existing studies of public perception and drawing analogies from other risk technologies, this paper explores the public positions on research and implementation of geoengineering as a means to combat climate change. Existing studies on geoengineering perceptions show low levels of awareness and a lack of knowledge. Hence, existing attitudes on geoengineering can be judged instable and stimulus-dependent. When judged in isolation, at least one third favors the use of geoengineering technologies preferring CDR over SRM technologies; when judged in comparison to other climate mitigation options, approval rates lose considerably support. Moreover, people seem to cautiously support research but oppose deployment while attitude formation depends on personal values and belief systems. The results of the empirical studies were fed into a Delphi workshop with experts for reflecting on the future development of public opinion and for designing a communication and public involvement process that corresponds to the empirical insights gained from the perception studies. 相似文献
25.
FTIR spectroscopy of Ti-chondrodite,Ti-clinohumite,and olivine in deeply subducted serpentinites and implications for the deep water cycle 总被引:1,自引:0,他引:1
Tingting Shen Jőrg Hermann Lifei Zhang José Alberto Padrón-Navarta Jing Chen 《Contributions to Mineralogy and Petrology》2014,167(4):1-15
Separated olivine grains from a deeply subducted serpentinized wehrlite (Changawuzi in the western Tianshan ultrahigh-pressure belt, China) were analysed with unpolarized transmission FTIR and the Ti contents were determined using LA-ICP-MS. The major bands in the olivine spectra display striking similarities to Ti-clinohumite and are interpreted as OH in lamellae. The quantification of the water content in lamellae requires calibration of the IR-absorption for such bands. We have obtained a new absorption coefficient for Ti-clinohumite of 0.125+/?0.017 ppm cm2 based on polarized FTIR measurements on three orthogonal sections through a large single crystal of Ti-clinohumite from Val Malenco, which has a known water content of 1.53 wt%. The resulting water content in olivine using this calibration factor ranges from 440 to 2,600 ppm and correlates positively with the Ti content that ranges from 130 to 1,400 ppm. For the quantification of the water content in Ti-chondrodite and Ti-clinohumite that are associated with olivine, we developed a new method using attenuated total reflectance FTIR spectroscopy. Ti-chondrodite and Ti-clinohumite display similar IR bands at ~3,562, 3,525 and ~3,583–3,586 cm?1. As in olivine, the water content and Ti content correlate in both Ti-clinohumite and Ti-chondrodite, indicating an intergrowth of these minerals, which has been confirmed by TEM analyses. Our results confirm previous suggestions that there is a strong correlation between the Ti content of ultramafic rocks and their capacity to transport water to the deeper mantle in subduction zones beyond conditions where hydrous phases are stable. 相似文献
26.
27.
Starting from the occurrence of a zonal Walker circulation supplementing the meridional Hadley cell, the concept of ultralong waves with diagonal upper troughs extending far into the Tropics is stressed. The model of equatorial upwelling with air‐sea coupling is critically discussed and a modification proposed. An intensification of the subtropical jet at the peak of the 1972 El Niño (as suggested by Rowntree's model calculations) has been verified. Empirical studies deal with the large interannual and interdecadal variations of the energy fluxes at the air‐sea interface; time variations of the oceanic evaporation and sensible heat flux are greater than expected. Using spectrum analysis, the occurrence of a 5‐year periodicity in equatorial rainfall of the Pacific and Indonesia is demonstrated, together with a marked phase shift along the NE coast of New Guinea. 相似文献
28.
Hermann Hügenell 《Astrophysics and Space Science》1989,160(1-2):231-239
The Central-Axis Reflector, the design principle which is presented below is a segmented-mirror telescope. The inventions relate mainly to the optical system and to the tracking apparatus.A large number of small individual mirror bodies, ground off-axis (hexagonal/polygonal) produce one primary mirror with closed circular aperture when joined together.The overall design of the tracking apperatus results directly —and thus without unnecessary adornment — from the two planes of to aminimum but which are required for tracking of the telescope.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 2, 1988. 相似文献
29.
Hermann Aldinger 《Mineralogy and Petrology》1965,10(1-4):61-68
Zusammenfassung Im Ablagerungsbecken des Unteren Lias und Dogger dürften, wenn nicht Ebbe und Flut, so doch aperiodische Schwankungen des Meeresspiegels um mehrer Meter aufgetreten sein. Durch die Spiegelschwankungen wird das Sedimentgefüge in von Ort zu Ort wechselndem Ausmaß geändert, austretendes Porenwasser trägt außerdem zur Sedimentbildung bei.
Mit 1 Textabbildung
Herrn Professor Dr.F. Machatschki zum 70. Geburtstag gewidmet. 相似文献
Summary Aperiodic fluctuations of sea level, caused by wind, during some periods of Lower and Middle Jurassic in Southern Germany should have had similar effects as tides in Watten today, altering the fabric of sediments and bringing pore water low in pH and eH to the surface. Glauconite and Chamosite may have been formed by mixing of normal sea water with pore water.
Mit 1 Textabbildung
Herrn Professor Dr.F. Machatschki zum 70. Geburtstag gewidmet. 相似文献
30.
Recent tectonic models of the Alpine-Carpatho-Pannonian region (ALCAPA) assume a large eastward shift of the Transdanubian Range domain, in the Cenozoic. Since palaeomagnetism is one of the most powerful tools in solving geodynamic processes, the authors present an approach to the escape problem by using all available and relevant palaeomagnetic data. This data set demonstrates consistency with models put forward by geologists for Jurassic and older ages. From the mid-Jurassic on the Northern Calcareous Alps (NCA) did not share the rotations of the Transdanubian Range domain and of the Southern Alps. After individual movements from Neocomian to Miocene, the Transdanubian Range domain must have drifted northward in the mid-Miocene up to the Southern margin of the Northern Calcareous Alps, before starting the escape in the geologists' definition. 相似文献