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11.
Prof. Dr. Herbert Straka 《International Journal of Earth Sciences》1962,51(2):517-530
Ohne ZusammenfassungProf.Gunnar Erdtman, Stockholm, danke ich für die freundliche Überlassung der meisten Abbildungsvorlagen. 相似文献
12.
Prof. Dr. Luigi Castoldi 《Pure and Applied Geophysics》1953,26(1):1-9
Riassunto L'ipotesi di costanza della massa totale dell'Universo, sostituita a quella diA. Friedmann di pressione elettromagnetica nulla, conduce a una densità materiale ed a una età dell'Universo più conformi ai risultati astronomici.
Summary A new relativistical theory of a time-variable Universe is proposed, founded on the hypothesis of a constant total mass. Results are deduced in better agreement whith astronomical data than byA. Friedmann theory founded on the hypothesis of vanishing electromagnetical pressure.相似文献
13.
Ahmet Güllü Ercan Yüksel Cem Yalçın A. Anıl Dindar Hasan Özkaynak Oral Büyüköztürk 《地震工程与结构动力学》2019,48(1):27-45
Input energy is the principal component of the energy balance equation. It is beneficial to determine, through its components, how the recoverable and irrecoverable energies are distributed within the structural elements. Several equations and attenuation relations to define mass-normalized input energy spectra exist in the literature. They are mainly proposed for elastic systems subjected to far-fault EQs. There is a lack of experimental verification of these proposed spectra. In this paper, experimental assessment was performed to the existing spectra, and further improvements were accomplished. For this purpose, steel cantilever columns were tested on the shake table for two specific historical EQs coincidently having similar spectral acceleration values. Based on the experimental results, a three-part mass-normalized relative input energy spectrum was formulated including soil type, EQ (corner period, intensity, duration, spectral acceleration, and velocity), and structural behavioral characteristics (period and structural damping). The proposed input energy spectrum was experimentally calibrated and numerically validated for various EQs featuring near- and far-field types. Analytical and experimental comparisons were made between the previously developed spectrum and the newly proposed one. The validation studies and the statistical evaluations exposed that the proposed spectrum yielded better agreement with the experimental and numerical results. 相似文献
14.
A new technique to determine geoid and orthometric heights from satellite positioning and geopotential numbers 总被引:1,自引:0,他引:1
L. E. Sjöberg 《Journal of Geodesy》2006,80(6):304-312
This paper takes advantage of space-technique-derived positions on the Earth’s surface and the known normal gravity field to determine the height anomaly from geopotential numbers. A new method is also presented to downward-continue the height anomaly to the geoid height. The orthometric height is determined as the difference between the geodetic (ellipsoidal) height derived by space-geodetic techniques and the geoid height. It is shown that, due to the very high correlation between the geodetic height and the computed geoid height, the error of the orthometric height determined by this method is usually much smaller than that provided by standard GPS/levelling. Also included is a practical formula to correct the Helmert orthometric height by adding two correction terms: a topographic roughness term and a correction term for lateral topographic mass–density variations. 相似文献
15.
Erika Böhm-Vitense 《Astrophysics and Space Science》1969,4(2):233-239
For the case of isotropic coherent scattering plus absorption a simple expression is given (Equation 12) to compute the mean intensity of the radiationJ
v
(as a function of optical depth
v
) if the scattering coefficient
v
, the absorption coefficientK
v
and the Planck functionB
v are given as a function of depth. In general the accuracy of this approximation is of the order of a few percent.A fairly simple temperature-correction procedure for the case when scattering is important is described. 相似文献
16.
17.
Prof. Dr. Mircea D. Ilie 《International Journal of Earth Sciences》1970,59(2):605-623
Résumé À la constitution des Carpates Roumaines participent les plissements hercyniens et carpatiques.Les déformations géométriques hercyniennes ont résulté des plissements profonds déterminés par le métamorphisme régional. Elles ont influencé d'une manière de plus en plus atténuée les plissements carpatiques. Pendant le paroxisme mésocrétacé, la tectonique carpatique a engendré des nappes de décollement et des glissements grâce à un simple mécanisme, expliqué par la pesanteur.Les nappes à vergences anticarpatiques se sont formées pendant la phase laramienne. Elles sont également le résultat de la pesanteur associée à l'action de la sous-poussée.Les nappes polygénétiques sont les nappes les plus jeunes et caractérisent les zones du Flysch des Carpates Orientales.Pendant le Tertiaire, une tectonique cassante a prédominé dans les Carpates.
The Romanian Carpathians consist of three subdivisions, each of them having its tectonical features, namely: Eastern Carpathians, Southern Carpathians and Apuseni Mountains.Their architecture consists of Hercynian and Carpathian foldings. The Hercynian tectonics is due to the deep foldings during the metamorphism which called forth the metanappes. The Hercynian foldings have printed their characters into the Carpathian tectonics and into the evolution of the palaeomesozoical sedimentary zones.During the mesocretaceous phase, the gravitational tectonics develop into the Carpathian realm, generating the gravitational nappes of the Metalliferous Mountains, the Raru-Hsma massif and the Perani Mountains.The overthrusts took place at the surface and are not due to the lateral contraction of the rocks in the depth.The anticarpathian vergences are characteristic for the Laramian nappes.The Flysch tectonics is characterized by polygenetic nappes, formed during a long period and developed all along the chain.The ruptural tectonics developed in the Romanian Carpathians during Tertiary.
Zusammenfassung Die rumänischen Karpaten lassen sich in drei Einheiten teilen, jede mit ihrer Besonderheit: Ostkarpaten, Südkarpaten und Apuseni-Gebirge. Ihr Bau besteht aus herzynischen und karpatischen Elementen. Die herzynische Tektonik ist die Folge der während der Metamorphose entstandenen Tieffaltungen, welche Metadecken hervorgebracht haben. Die herzynischen Faltungen zeigen sich im karpatischen Bau und in der Ablagerungsgeschichte. Während der mittelkretazischen Faltungsbewegungen hat die Abscherungs- und Fließtektonik das karpatische Gebiet ergriffen und das Entstehen der Schweredecken im Erzgebirge, in den Raru- und Hsma-Massiven sowie im Perani-Gebirge bedingt. Die Decken sind die Folge der in der Nähe der Erdoberfläche ablaufenden Bewegungen und keineswegs des seitlichen Druckes der Tiefgesteine. Die laramischen Decken sind durch antikarpatische Vergenzen charakterisiert und auf die Unterschiebungen der alten Blöcke zurückzuführen. Die Tektonik des Flysches zeichnet sich durch polygenetische Decken aus, die sich während mehrerer Perioden, entlang dem Faltenstreichen, entwickelt haben. Die Bruchtektonik setzte in den rumänischen Karpaten erst während des Neozoikums ein.
. , , . , , . . .相似文献
18.
Stokes' formula from 1849 is still the basis for the gravimetric determination of the geoid. The modification of the formula,
originating with Molodensky, aims at reducing the truncation error outside a spherical cap of integration. This goal is still
prevalent among various modifications. In contrast to these approaches, some least-squares types of modification that aim
at reducing the truncation error, as well as the error stemming from the potential coefficients, are demonstrated. The least-squares
estimators are provided in the two cases that (1) Stokes' kernel is a priori modified (e.g. according to Molodensky's approach)
and (2) Stokes' kernel is optimally modified to minimize the global mean square error. Meissl-type modifications are also
studied. In addition, the use of a higher than second-degree reference field versus the original (Pizzetti-type) reference
field is discussed, and it is concluded that the former choice of reference field implies increased computer labour to achieve
the same result as with the original reference field.
Received: 14 December 1998 / Accepted: 4 October 1999 相似文献
20.
Levente Füköh 《GeoJournal》1995,36(2-3):255-259
Based on phylogenetical, palaeoecological and biostratigraphical studies on the Holocene malacofauna of Hungarian medium high mountains and flatlands, four faunal periods could be recognised in the mountains, while three ones on the flat regions. They are defined by correlation (using anthracotomical, palynological, vertebrate palaeontological, archaeological and radiometric data, as well as by the Central European malacozones) as biozones of regional value.The mollusc fauna may be regarded as the main palaeoecological indicator for the Hungarian Quaternary, because it is generally abundant, in contrast to the vertebrate fauna. On the other hand, the Hungarian Quaternary fauna mostly consists of species still living in the area. The ecological demands of recent species are generally well known. Most of the ecological data about the Quaternary formations were yielded by the examination of the Hungarian mollusc fauna.The Quaternary mollusc fauna is not only suitable for palaeoecological reconstructions but it helps in the stratigraphical division of the sequences, as well, mainly due to Endre Krolopp's activity (Krolopp 1983). This study and investigations of Holocene molluscs enabled us to make an attempt (Füköh 1990) in describing the history of the last ten thousand years. 相似文献