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161.
In this work, the GOCE satellite orbit is described in the aspect of perturbations in the Keplerian osculating elements. The
perturbations come from the Earth and ocean tides, the gravitation of the Moon, the gravitation of the Sun, the gravitation
of planets and Pluto, and the relativity effects. These perturbations are computed for the 30-day interval with a sampling
of 2 min. To obtain the simulated orbit, the Cowell numerical integration method of 8th order is used. The first part of the
work contains the root mean square (RMS) values of aforementioned perturbations due to the specified forces. The perturbations
were compared taking into account their RMS characteristics. 相似文献
162.
Ewa Słaby Michał Śmigielski Tomasz Śmigielski Andrzej Domonik Klaus Simon Andreas Kronz 《Contributions to Mineralogy and Petrology》2011,162(5):909-927
As has been demonstrated in recent years, the heterogeneities of coeval magmas can be more successfully revealed by zoned
megacrysts rather than by analysis of the whole rocks hosting them. Here, the geochemical heterogeneities of feldspar megacrysts
from the Karkonosze granite, Poland, are investigated by LA-ICP-MS. The crystals are the product of migration and growth in
regions of poorly mixed magmas. 3D-modeling of the Ba, Sr, and Rb distributions emphasizes the importance of micro-domain
growth morphologies. Two models of element behavior—a relative concentration model and a composition gradient model—provide
a potentially effective tool for tracking the mixing process on a microscale. Measured concentrations of elements of different
mobilities do not agree with what might be expected from the mixing of two end-member magmas. If mixing was the only process
occurring, linear correlations between the concentrations of any two elements should be observed; this, however, is not the
case. For combinations of any two of the three elements, modeling reveals differing non-linear correlations between concentrations.
The megacryst heterogeneities provide an insight into how mixing magmas are chaotically advected to growing crystals and the
degree of inter-magma element exchange between the magmas. 相似文献
163.
Krystian Konieczyński Andrzej Pisera Maria Aleksandra Bitner Andras Galácz 《Swiss Journal of Geoscience》2013,106(1):109-118
The Bathonian crinoid fauna that occurs in red nodular limestone and argillaceous limestones from the Hidas Valley, Mecsek Mts (southern Hungary) consists of three isocrinid and six cyrtocrinid species. Isocrinids are represented by Balanocrinus inornatus (d’Orbigny), B. berchteni Hess and Pugin and Balanocrinus sp. Cyrtocrinids are represented by Phyllocrinus stellaris Zar?czny, P. birkenmajeri G?uchowski, P. malbosianus d’Orbigny, Apsidocrinus sp., Lonchocrinus sp., and the new species Psalidocrinus hidasinus sp. nov. This last species is the earliest occurrence of the genus Psalidocrinus previously known from the Early Tithonian to Valanginian. This is the first crinoid fauna described from the Middle Jurassic (Bathonian) of Hungary. The co-occurrence of isocrinids and cyrtocrinids indicates an environment subject to weak currents. The stratigraphical and geographical distribution of the identified cyrtocrinid genera and species suggests a Tethyan origin and subsequent migration to the northern Tethyan shelf. 相似文献
164.
165.
Jacek Andrzej Urbanski 《International journal of geographical information science》2013,27(7):723-730
This paper advocates the use of GIS for the evaluation of the vulnerability of coastal waters and presents a method for mapping their vulnerability to algal blooms. The method incorporates probability mapping of parameters used to describe coastal waters and fuzzy sets. To allow the modelling of processes where some components cannot substitute for other components the 'no trade off' convex combination formula is proposed. The maps of vulnerability for the Gulf of Gdansk, which were created using this method, may be used to find out which rivers and water discharges play a dominant role in eutrophication. 相似文献
166.
Jacek Grabowski János Haas Emö Márton Andrzej Pszczółkowski 《Studia Geophysica et Geodaetica》2010,54(1):1-26
Jurassic-Cretaceous sediments of Transdanubian Range in Northern Hungary mostly retain their primary magnetizations and are
suitable for detailed bio- and magnetostratigraphic studies. The Lókút section, 13 m in thickness, is localized in the central
part of the Transdanubian Range. It contains the Jurassic/Cretaceous boundary in pelagic carbonate facies. Although the colour
of the rocks changes from reddish-pinkish in the bottom to almost white at the top of the section, magnetite was identified
as a magnetic carrier without evidence of hematite. Integrated bio- and magnetostratigraphical investigations resulted in
construction of chronostratigraphical scheme. The section, embraces magnetozones from M21r to M18r, of upper Lower Tithonian
(Parastomiosphaera malmica Zone) to Lower Berriasian age (Calpionella alpina Subzone). Sedimentation rate of pelagic limestones
increased from 1–3 m/My during Tithonian to 5–7 m/My during Berriasian. The sedimentation rate and its changes up the section
are comparable to those from the Jurassic/Cretaceous boundary sections of Trento plateau (Southern Alps, Italy) — sedimentary
environments of Trento plateau and central Transdanubian Range in that time might be similar. Sedimentation rate within Umbrian
Apennine basins and Križna unit in the Western Tatra Mts. seems significantly higher. Analysis of rock magnetic parameters
reveals that detrital input was much lower into the Lókút section than into Križna basin in the Tatra Mts. (Zliechov trough).
Increase of sedimentation rate occurs in both sections in the Upper Tithonian — Lower Berriasian. It coincides with the onset
of calpionellid limestone facies and is related to increased productivity of calcareous micro- and nannoplankton. Detailed
correlation of both sections basing on rock magnetic parameters and susceptibility changes is, however, not possible. They
are dependent mostly on the local sedimentary conditions (Bakony Mts. — deep water plateau; Križna unit — deep water trough)
and correlation with any “global” paleoenvironmental (climatic, eustatic) trends is not straightforward. 相似文献
167.
New Methods for Modeling Laterolog Resistivity Corrections 总被引:1,自引:1,他引:0
Jadwiga Anna Jarzyna Adam Cichy Dezső Drahos Attila Galsa Maria Joanna Bała Andrzej Ossowski 《Acta Geophysica》2016,64(2):417-442
The paper presents methods for laterolog response modeling. In Coulomb’s charges method, Laplace’s equation is solved for the electric field distribution in rock medium with internal boundaries between different resistivity layers. There, the boundary problem is reduced to Fred-holm integral equation of the second kind. The second method uses a finite element array to model apparent resistivity from laterolog. The task is treated as DC problem and the Laplace equation is solved numerically. The presented methods were applied to borehole data covering a typical stratigraphie section of the Fore-Sudetic Monocline in southwestern Poland. Apparent resistivity was calculated using the Coulomb’s charges method and alternatively modeled using a finite element method which gave similar results. Then, a series of linear corrections for borehole, shoulder bed, and filtration effects for apparent resistivity obtained by the Coulomb’s charges method demonstrated the feasibility of calculating true resistivity of virgin and invaded zones. The proposed methods provide a flexible solution in modeling which can be adapted to other logs. 相似文献
168.
Prospects for Solar and Space Weather Research with Polish Part of the LOFAR Telescope 总被引:1,自引:1,他引:0
Bartosz P. Dąbrowski Andrzej Krankowski Leszek Błaszkiewicz Hanna Rothkaehl 《Acta Geophysica》2016,64(3):825-840
The LOw-Frequency ARray (LOFAR) is a new radio interferometer that consists of an array of stations. Each of them is a phase array of dipole antennas. LOFAR stations are distributed mostly in the Netherlands, but also throughout Europe. In the article we discuss the possibility of using this instrument for solar and space weather studies, as well as ionosphere investigations. We are expecting that in the near future the LOFAR telescope will bring some interesting observations and discoveries in these fields. It will also help to observe solar active events that have a direct influence on the near-Earth space weather. 相似文献
169.
Andrzej Bobojć 《Acta Geophysica》2016,64(2):521-540
The possibility of improving the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) mission satellite orbit using gravity gradient observations was investigated. The orbit improvement is performed by a dedicated software package, called the Orbital Computation System (OCS), which is based on the classical least squares method. The corrections to the initial satellite state vector components are estimated in an iterative process, using dynamic models describing gravitational perturbations. An important component implemented in the OCS package is the 8th order Cowell numerical integration procedure, which directly generates the satellite orbit. Taking into account the real and simulated GOCE gravity gradients, different variants of the solution of the orbit improvement process were obtained. The improved orbits were compared to the GOCE reference orbits (Precise Science Orbits for the GOCE satellite provided by the European Space Agency) using the root mean squares (RMS) of the differences between the satellite positions in these orbits. The comparison between the improved orbits and the reference orbits was performed with respect to the inertial reference frame (IRF) at J2000.0 epoch. The RMS values for the solutions based on the real gravity gradient measurements are at a level of hundreds of kilometers and more. This means that orbit improvement using the real gravity gradients is ineffective. However, all solutions using simulated gravity gradients have RMS values below the threshold determined by the RMS values for the computed orbits (without the improvement). The most promising results were achieved when short orbital arcs with lengths up to tens of minutes were improved. For these short arcs, the RMS values reach the level of centimeters, which is close to the accuracy of the Precise Science Orbit for the GOCE satellite. Additional research has provided requirements for efficient orbit improvement in terms of the accuracy and spectral content of the measured gravity gradients. 相似文献
170.