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971.
¶rt;mam mam a¶rt;u, m u a nuu mauu nu¶rt; 1970–1977. nauaumGs 11 No 131, 201 uGs 15 No 228. a¶rt; ¶rt;uam mauau ¶rt;u um. ¶rt;uu au naam nuu nu¶rt; ma. 2,uuu au ma. 3.
Paper presented at the IUGG XVII Plenary Meeting, Canberra, Dec. 1979. 相似文献
Paper presented at the IUGG XVII Plenary Meeting, Canberra, Dec. 1979. 相似文献
972.
u¶rt;m ¶rt; anum¶rt;-amm aamumu maum a aa nu mummu (). ma¶rt;am aamumu uu mau auma uu am auu a uu aaa aa. 相似文献
973.
V. B. Buryanov V. V. Gordienko N. I. Pavlenkova Reviewer I. Pšenčík 《Studia Geophysica et Geodaetica》1980,24(2):114-123
m¶rt; amamu ¶rt;uau nma nauua ¶rt; a n amu . n ¶rt;a uu u¶rt;au,aumuu u mn nma. mam maa auum ¶rt; m u nmm u¶rt;ua n¶rt;a u a maa a umua a nam . ¶rt; nmm amuu n¶rt;m uu 3,3/
3
, n¶rt; ¶rt;uuuau u na¶rt;uau mu a anma ¶rt; 3,2/
3
. ¶rt; n¶rt;uu a¶rt;u aau mum nm, maumaa ¶rt;¶rt;m aama u ¶rt; amu .
Presented at the KAPG Symposium Problems of Interpretation and Construction of Physical Models of Litosphere, Liblice (CSSR), March 6–10, 1978. 相似文献
Presented at the KAPG Symposium Problems of Interpretation and Construction of Physical Models of Litosphere, Liblice (CSSR), March 6–10, 1978. 相似文献
974.
975.
976.
977.
Résumé Les auteurs utilisent toutes les données chimiques, volcanologiques, chronologiques et tectonophysiques fournies pour un certain nombre de massif continentaux (Mont-Dore et autres). La synthèse de toutes ces études montre qu'il existe deux magmas continentaux indépendants: le magma basaltique venant du manteau (sima) et le magma rhyolitique fourni par la croûte supérieure (sial). Le mélange de ces deux magmas et l'action secondaire de la' gravité et de la pneumatolyse expliquent logiquement la totalité des phénomènes géochimiques des volcans continentaux.
The authors used all the chemical, volcanological, chronological and tectonophysical data supplied for a certain number of continental mountain massifs (Mont-Dore and others). The synthesis of these studies shows that there are two independent continental magmas: the basaltic magma coming from the mantle (sima) and the rhyolitic magma supplied by the upper crust (sial). The mixing of these two magmas, with the secondary action of gravity and pneumatolysis logically explains the totality of the geochemical phenomena in continental volcanoes.
Zusammenfassung Die Autoren benutzten alle chemischen, vulkanologischen, chronologischen und tektonisch-physikalischen Daten, die von einer bestimmten Anzahl von kontinentalen Massiven (Mont-Dore und andere) entnommen wurden.Das Ergebnis dieser Studien zeigt, daß es zwei voneinander unabhängige kontinentale Magmen gibt.Das basaltische Magma, vom Sima stammend, und das rhyolitische Magma aus der oberen Sial-Kruste. Die Vermischung dieser beiden Magmen und die zusätzliche Wirkung der Gravitation und Pneumatolyse erklären auf natürliche Weise die Gesamtheit der geochemischen Phänomene des kontinentalen Vulkanismus.
. , .相似文献
978.
979.
The spectral characteristics of the δ18O isotopic ratio time series of the Quelccaya ice cap summit core are investigated with the multi taper method (MTM), the
singular spectrum analysis (SSA) and the wavelet transform (WT) techniques for the 500 y long 1485–1984 period. The most significant
(at the 99.8% level) cycle according to the MTM F-test has a period centered at 14.4 y while the largest variance explaining
oscillation according to the SSA technique has a period centered at 12.9 y. The stability over time of these periods is investigated
by performing evolutive MTM and SSA on the 500 y long δ18O series with a 100 y wide moving window. It is shown that the cycles with largest amplitude and that the oscillations with
largest extracting variance have corresponding periods aggregated around 13.5 y that are very stable over the period between
1485 and 1984. The WT of the same isotopic time series reveals the existence of a main oscillation around 12 y which are also
very stable in time. The relation between the isotopic data at Quelccaya and the annual sea surface temperature (SST) field
anomalies is then evaluated for the overlapping 1919–1984 period. Significant global correlation and significant coherency
at 12.1 y are found between the isotopic series and the annual global sea surface temperature (GSST) series. Moreover, the
correlation between the low (over 8 y) frequency component of the isotopic time series and the annual SST field point out
significant values in the tropical North Atlantic. This region is characterized by a main SST variability at 12.8 y. The Quelccaya
δ18O isotopic ratio series may therefore be considered as a good recorder of the tropical North Atlantic SSTs. This may be explained
by the following mechanism: the water vapor amount evaporated by the tropical North Atlantic is function of the SST. So is
the water vapor δ18O isotopic ratio. This water vapor is advected during the rainy season by northeast winds and precipitates at the Quelccaya
summit with its tropical North Atlantic isotopic signature. It is also suggested from this described stability of the decadal
time scale variability observed in the Quelccaya isotopic series, that the decadal time scale GSST variability was also stable
during the last five centuries.
Received: 12 February 1997 / Accepted: 9 September 1997 相似文献
980.
—Approximate PP plane wave displacement coefficients of reflection and transmission for weak contrast interfaces separating weakly but arbitrarily anisotropic elastic media are presented. The PP reflection coefficient for such an interface has been derived recently by Vavry?uk and P?en?ík (1997). The PP transmission coefficient presented in this paper was derived by the same approach. The coefficients are given as a sum of the coefficient for the weak contrast interface separating two nearby isotropic media and a term depending linearly on contrasts of the so-called weak anisotropy (WA) parameters (parameters specifying deviation of properties of the medium from isotropy), across the interface. While the reflection coefficient depends only on 8 of the complete set of the WA parameters describing P-wave phase velocity in weakly anisotropic media, the transmission coefficient depends on their complete set. The PP reflection coefficient depends on "shear-wave splitting parameter" γ. Tests of accuracy of the approximate formulae are presented on several models. 相似文献