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121.
Walter Müller 《Pure and Applied Geophysics》1967,66(1):169-182
Zusammenfassung Nach allgemeinen und quantitativen Angaben über die Ursachen der Zu-und Abnahmen der Kondensationskerndichte wird auf die natürliche und industrielle Kernproduktion verwiesen. Auf Grund einjähriger Morgen- und Mittagsbeobachtungen in Wien mit einem Pollak-Kondensationskernzähler wird besonders die Sedimentation, der Washout- und Rainouteffekt, der Einfluss von Austausch und Windadvektion sowie der Jahres- und Wochengang besprochen.
Summary General as well as quantitative details of reasons of the variations of the density of condensation nuclei is mentioned. Based on one year's records of observations in the morning and at noon in Vienna, executed by menas of a Pollak-condensation nucleus counter especially the effects of sedimentation, washout, rainout, exchange, wind advection, annual and weekly variation is discussed.相似文献
122.
Walter Weingart 《International Journal of Earth Sciences》1955,44(1):173-192
Zusammenfassung Stratigraphische und tektonische Untersuchungen im Gebiet zwischen Rheinbrohl/Brohl im NW und Leutesdorf/Namedy im SE erbrachten den Nachweis einer Großmulde aus Mittleren Siegener Schichten, deren Kern bei Oberhammerstein den Rhein quert. Die HENKE'sche Annahme eines Hönningen-Seifener Sattels im NW unseres Gebietes konnte bestätigt werden. Aus dem gegenseitigen Verhalten zwischen Faltung und Brüchen verschiedener Art ließ sich eine Altersfolge entwickeln, wobei die Einzelphasen sich einander zeitlich überschneidend ablösen. Diese zeitliche Folge wird von Falte zu Falte von den örtlichen Faktoren modifiziert, so durch die Verzopfung zweier Einzelfalten, wie an einem gut überschaubaren Beispiel gezeigt wird. 相似文献
123.
Walter Stephan 《International Journal of Earth Sciences》1959,48(1):92-95
Zusammenfassung Auswirkungen der saalischen Phase sind nun auch im Stockheimer Becken erstmals festgestellt. In der Hauptsache ist in diesem Gebiet jedoch mit orogenetischen Bewegungen im Unterrotliegenden selbst zu rechnen. — Der Vulkanismus entwickelte sich im Becken bzw. an seinen Rändern vermutlich bereits im jüngsten Oberkarbon (1. Phase, am stärksten ausgebildet) und hält dann im Unterrotliegenden an (2. Phase, evtl. noch Gehrener Stufe). Aus dem mittleren Rotliegenden sind bisher nur Porphyr-Fanglomerate angeführt worden. Allerdings muß berücksichtigt werden, daß deren Neubearbeitung noch nicht abgeschlossen ist und das Stockheimer Becken ohnehin nur einen kleinen Ausschnitt aus der Gesamtentwicklung am Südwestrand des Frankenwaldes darstellt. Mit einem Vulkanismus im mittleren Rotliegenden (3. Phase, ? Goldlauterer Stufe) ist demnach auch hier noch zu rechnen. 相似文献
124.
During the last two decades, there has been growing interest in the integration of existing ideas and data to produce new
synthetic models and hypotheses leading to discovery and advancement in estuarine and coastal science. This essay offers an
integrated definition of what is meant by synthesis research and discusses its importance for exploiting the rapid expansion
of information availability and for addressing increasingly complex environmental problems. Approaches and methods that have
been used in published synthetic coastal research are explored and a list of essential steps is developed to provide a foundation
for conducting synthetic research. Five categories of methods used widely in coastal synthesis studies are identified: (1)
comparative cross-system analysis, (2) analysis of time series data, (3) balance of cross-boundary fluxes, (4) system-specific
simulation modeling, and (5) general systems simulation modeling. In addition, diverse examples are used to illustrate how
these methods have been applied in previous studies. We discuss the urgent need for developing curricula for classroom and
experiential teaching of synthesis in coastal science to undergraduate and graduate students, and we consider the societal
importance of synthetic research to support coastal resource management and policy development. Finally, we briefly discuss
the crucial challenges for future growth and development of synthetic approaches to estuarine and coastal research. 相似文献
125.
126.
Pradeep Talwani 《Journal of Seismology》2017,21(1):47-68
Continental intraplate regions are characterized by uniform stresses over thousands of kilometers. Local stresses, with wavelengths of tens to hundreds of kilometers can accumulate at inhomogeneities lying within these regional fields. A variety of geological structures, herein called local stress concentrators (LSCs), act as elastic inhomogeneities. The temporal buildup of stress depends on the particular structure and its geometrical relationship with the regional stress field. The interaction of the local and the regional stress fields can result in the rotation of the latter over wavelengths of tens to hundreds of kilometers. This rotation can be detected by direct measurement or from seismicity data. Intraplate earthquakes (IPEs) result when the local stresses become comparable with their regional counterparts, i.e., hundreds of megapascals. Globally, most of the seismic energy release associated with IPEs occurs within old rifts which contain LSCs most favorable for stress buildup by stress inversion. Of the various LSCs, stepover en echelon faults are associated the largest IPEs. In low tectonic strain rate regions, IPEs are associated with larger stress drops. With the availability of a variety of LSCs, there is generally an absence of repeat earthquakes. Instead, successive earthquakes occur on different structures, leading to the observation of “roaming” earthquakes. These observations suggest a need for a reevaluation of seismic hazard estimation techniques. This study addresses some of these facets of the nature of IPEs with global examples, including a unique, detailed seismicity and geodetic data set collected in a dozen years following the 2001 M 7.7 Bhuj earthquake in western India. 相似文献
127.
Walter Wahl 《International Journal of Earth Sciences》1942,32(4-5):550-562
Ohne Zusammenfassung 相似文献
128.
Roland Walter 《Astrophysics and Space Science》2007,309(1-4):5-9
INTEGRAL is operational since more than three years and producing high quality data that allows to detect fainter new hard
X-ray sources. The new sources, identified until now, are mostly active galactic nuclei and absorbed or transient high mass
X-ray binaries. TeV emission could be expected from the new high mass X-ray binaries accreting dense clumps of stellar wind.
INTEGRAL sources with TeV counterparts are discussed.
Based on observations with INTEGRAL, an ESA project with instruments and science data centre funded by ESA member states (especially
the PI countries: Denmark, France, Germany, Italy, Switzerland, Spain), Czech Republic and Poland, and with the participation
of Russia and the USA. 相似文献
129.
A detector sharing the orbital rate of Venus has a unique perspective on solar periodicities. Fourier analysis of the 8.6 year record of solar EUV output gathered by the Langmuir probe on Pioneer Venus Orbiter shows the influences of global oscillation modes located in the convective envelope and in the radiative interior. Seven of the eight lowest angular harmonic r-mode families are detected by their rotation rates which differ almost unmeasurably from ideal theoretical values. This determines a mean sidereal rotation rate for the envelope of 457.9 ± 2.0 nHz which corresponds to a period of 25.3 days. Many frequencies are aliased at ± 106 nHz by modulation from the lowest angular harmonic r-mode in the envelope. The rotation of this mode seems slightly retrograde, -1.5 ± 2.0 nHz, but small positive values are not excluded. We confirm that the rotation of the radiative interior, 381 nHz, is slower than the envelope by detecting g-mode frequencies for angular harmonics, 2 l 6, and a possible first detection of the rotation rate for the l = 1 case. Solar EUV lacks the sudden darkenings (dips) shown by visible irradiance; vortex cores in the photosphere and below are again suggested as a possible explanation. 相似文献
130.
G. J. Bendo D. Calzetti C. W. Engelbracht R. C. Kennicutt Jr M. J. Meyer M. D. Thornley F. Walter D. A. Dale A. Li E. J. Murphy 《Monthly notices of the Royal Astronomical Society》2007,380(4):1313-1334
To study the distribution of star formation and dust emission within nearby galaxies, we measured five morphological parameters in the 3.6- and 24-μm wavebands for 65 galaxies in the Spitzer Infrared Nearby Galaxies Survey (SINGS) and eight galaxies that were serendipitously observed by SINGS. The morphological parameters demonstrate strong variations along the Hubble sequence, including statistically significant differences between S0/a-Sab and Sc-Sd galaxies. Early-type galaxies are generally found to be compact, centralized, symmetric sources in the 24-μm band, while late-type galaxies are generally found to be extended, asymmetric sources. These results suggest that the processes that increase the real or apparent sizes of galaxies' bulges also lead to more centralized 24-μm dust emission. Several phenomena, such as strong nuclear star formation, Seyfert activity, or outer ring structures, may cause galaxies to deviate from the general morphological trends observed at 24 μm. We also note that the 24-μm morphologies of Sdm-Im galaxies are quite varied, with some objects appearing very compact and symmetric but others appearing diffuse and asymmetric. These variations reflect the wide variation in star formation in irregular galaxies as observed at other wavelengths. The variations in the 24-μm morphological parameters across the Hubble sequence mirror many of the morphological trends seen in other tracers of the ISM and in stellar emission. However, the 24-μm morphological parameters for the galaxies in this sample do not match the morphological parameters measured in the stellar wavebands. This implies that the distribution of dust emission is related to but not equivalent to the distribution of stellar emission. 相似文献