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201.
A. M. Nikishin K. O. Sobornov A. V. Prokopiev S. V. Frolov 《Moscow University Geology Bulletin》2010,65(1):1-16
This paper presents characteristics of the structural regions surrounding the Siberian Platform and discusses the Vendian-present
time evolution of the Siberian Paleocontinent with the Siberian Craton making up its nucleus. It shows that the paleocontinent
underwent significant intraplate compressional deformations with vertical movements and formation of inversion structural
features within broad areas. Such epochs of deformation took place at the Riphean-Vendian time boundary, during the Late Paleozoic,
Late Triassic, Early Cretaceous, and during the Late Cenozoic. The principal rifting events took place during the Middle-Late
Devonian. The paper presents paleotectonic reconstructions of East Siberia at several key time intervals. 相似文献
202.
Yu. O. Kuzmin 《Izvestiya Physics of the Solid Earth》2009,45(11):973-986
Important problems of tectonophysical analysis of observational results in recent geodynamics are considered. The paradox
of low rates of recent horizontal deformations of the Earth’s surface is formulated. This paradox states that, according to
GPS measurements, the annual mean rates of relative deformations are 10−9–10−10 per year, whereas, according to ground-based geodetic and deformographic observations, the rates of recent horizontal deformations
of the Earth’s surface are on the order of 10−5–10−6 per year. This paradox is shown to appear as a result of the application of the procedure of averaging to the displacements
obtained on large measuring bases with a low degree of details of the time of observations.
It is established that, according to multiyear (over 40 years) data, the annual mean rate of deformation processes in the
Kopet Dagh seismically active region is 4 × 10−8 per annum along the vertical and 3.2 × 10−8 per year along the horizontal. 相似文献
203.
204.
The observations carried out using a seismogravimeter in St. Petersburg simultaneously with the variations of the Earth’s rotation rate determined based on the results of observations with radiotelescopes located at large distances from each other at the surface of the Earth are compared with each other. It is found that the simultaneous observations agree with each other in the daily variation dynamics. It is also found that the distribution of spectral components along the frequency axis in the spectra of these observations in a period range from 1 to 5 h corresponds to a long-known distribution of frequencies at which the Earth’s oscillations arise most often. It is also shown that the spectra in a period range from 1 to 5 h obtained in different years using the astronomical data, the superconducting gravimeter observations, and the seismogravimeter observations at points located at large distances from each other agree with each other very well. Individual oscillation components have comparable amplitudes and may not be of a tidal nature. An explanation that allows one to examine the entire body of obtained results from a unified perspective is proposed. 相似文献
205.
S. I. Abou-Elela S. A. El-Shafai M. E. Fawzy M. S. Hellal O. Kamal 《International Journal of Environmental Science and Technology》2018,15(4):743-754
Water heater manufacturing represents one sector of household electrical appliance industry. It includes several batch processes which resulted in a highly polluted wastewater as shock loads. The objective of this study was to manage the shock loads wastewater with a simple and cost-effective approach prior to final discharge into municipality. To achieve this objective, two approaches were studied. The first approach was the chemical treatment of the accumulated shock loads wastewater using alum and an anionic polymer. Although this approach produced a very high-quality effluent, it was economically and technically infeasible. The second approach was a controlled release of the shock loads to the normal daily discharge in a way that guarantees the compliance of the end-off-pipe with the National Regulatory Standards. This solution required establishment of an equalization tank for normal daily flow and a holding tank for controlled release of the shock loads. Mathematical calculations were carried out to determine the most violating parameters in order to calculate the mixing ratio the of shock loads with the normal daily flow. Full engineering design of the proposed solution was carried out. This approach was implemented and proved to be simple, easy to operate, cost-effective and can be replicated in similar batch processing manufacturing plants. 相似文献
206.
Joana M da Silva Antonina dos Santos Marina R Cunha Filipe O Costa Simon Creer Gary R Carvalho 《Marine Ecology》2013,34(2):157-170
Despite the high number of species and ecological diversity of pandalid shrimps, there has been no previous attempt to resolve evolutionary relationships of several genera using molecular tools. Although mitochondrial DNA cytochrome oxidase I (COI) is widely used in barcoding studies to delimit species boundaries, additional insights into phylogenetic affinities can be obtained, especially when used in combination with data from additional genes. The knowledge of molecular diversity is essential to understand phylogenetic relationships and will help systematic clarifications. Based on partial fragments of the 16S and COI genes, we have focused specifically on addressing the systematic relationships of the economically and ecologically important shrimp genus Plesionika within a framework of five genera from within the Pandalidae. Our results showed that species within Plesionika are substantially divergent when compared with other genera, exhibiting the highest average nucleotide divergence, with 0.1123 and 0.0846 in COI and 16S genes, respectively. In addition, sequence divergence was found to vary greatly within the genus Plesionika (COI/16S): 0.0247/0.0016 between Plesionika antigai and Plesionika heterocarpus and 0.1616/0.098 between Plesionika heterocarpus and Plesionika edwardsii. We did not find amino acid sequence divergence between P. heterocarpus and P. antigai compared with P. heterocarpus and P. edwardsii (8.10%, K2P distance). Three species of Plesionika (P. antigai, P. heterocarpus and Plesionika scopifera) appear well separated from other Plesionika species in both maximum likelihood and Bayesian analyses. The present study confirms the utility of COI over 16S as a genetic marker to resolve relationships between different species of Plesionika from the Northeast Atlantic and Mediterranean Sea, in addition to species delimitation. The findings highlight the need to further review paraphyly within Plesionika in an attempt to recognize a concordance in the evolutionary history of Plesionika with major ecological and geological events. 相似文献
207.
208.
V. S. Vechfinskii S. S. Solov’eva O. V. Gusev 《Izvestiya Physics of the Solid Earth》2008,44(3):256-259
Igneous rocks are shown to possess a magnetic fabric that admits the occurrence of giant Barkhausen jumps. It is also demonstrated that magnetic minerals of rocks can preserve information on a few magnetic fields (differing even in origin) and a few thermal magnetization temperatures. 相似文献
209.
Zubkova N. V. Pekov I. V. Chukanov N. V. Kasatkin A. V. Ksenofontov D. A. Yapaskurt V. O. Britvin S. N. Pushcharovsky D. Yu. 《Geology of Ore Deposits》2018,60(7):594-606
Geology of Ore Deposits - The crystal structure of lemanskiite is determined for the first time (R = 0.019) and the mineral is redefined. Its chemical formula, crystal system, space group and... 相似文献
210.
V. M. Zhurbas P. O. Zavialov A. S. Sviridov D. A. Lyzhkov E. E. Andrulionis 《Oceanology》2011,51(3):415-423
A numerical simulation has been undertaken to study the process of the transport of small river runoff by alongshore baroclinic
sea currents. The study is based on the implementation of the Princeton Ocean Model (POM) under the conditions of a circular
stratified basin whose surface is exposed to a transient tangential wind stress to form an alongshore baroclinic current.
A baroclinic current of the downwelling type (in the Northern Hemisphere directed to the left to a sea-viewing observer) was
shown to provide the carrying out of the river discharge from estuary’s vicinity more effectively than that of the upwelling
type (in the Northern Hemisphere directed to the right to a sea-viewing observer). 相似文献