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51.
Run Liu Shaw Chen Liu Ralph J. Cicerone Chein-Jung Shiu Jun Li Jingli Wang Yuanhang Zhang 《大气科学进展》2015,32(8):1027-1037
52.
Bi-Qing For Elizabeth M. Green Gilles Fontaine Scott Shaw 《Astrophysics and Space Science》2010,328(1-2):87-90
In this paper, we report a rare reflection effect eclipsing sdB+dM binary, 2M?1533+3759. It is the seventh eclipsing sdB+dM binary that has been discovered to date. This system has an orbital period of 0.16177042 day and a velocity semi-amplitude of 71.1 km?s?1. Using a grid of zero-metallicity NLTE model atmospheres, we derived T eff=29250 K, log?g=5.58 and [He/H]=?2.37 from spectra taken near the reflection effection minimum. Lightcurve modeling resulted in a system mass ratio of 0.301 and an orbital inclination angle of 86.6°. The derived primary mass for 2M?1533+3759, 0.376±0.055 M ⊙, is significantly lower than the canonical mass (0.48 M ⊙) found for most previously investigated sdB stars. This implies an initial progenitor mass >1.8 M ⊙, at least a main sequence A star and perhaps even one massive enough to undergo non-degenerate helium ignition. 相似文献
53.
The second and third recorded births of southern elephant seals Mirounga leonina on the mainland of New Zealand occurred at Kaikoura in mid‐October 1976. One female pup died within 14 d of birth and the other (sex unknown) disappeared from the region with its mother on 19 November 1976. 相似文献
54.
Tao Pei Carlo Ratti Shih-Lung Shaw Ting Li Chenghu Zhou 《International journal of geographical information science》2014,28(9):1988-2007
Land-use classification is essential for urban planning. Urban land-use types can be differentiated either by their physical characteristics (such as reflectivity and texture) or social functions. Remote sensing techniques have been recognized as a vital method for urban land-use classification because of their ability to capture the physical characteristics of land use. Although significant progress has been achieved in remote sensing methods designed for urban land-use classification, most techniques focus on physical characteristics, whereas knowledge of social functions is not adequately used. Owing to the wide usage of mobile phones, the activities of residents, which can be retrieved from the mobile phone data, can be determined in order to indicate the social function of land use. This could bring about the opportunity to derive land-use information from mobile phone data. To verify the application of this new data source to urban land-use classification, we first construct a vector of aggregated mobile phone data to characterize land-use types. This vector is composed of two aspects: the normalized hourly call volume and the total call volume. A semi-supervised fuzzy c-means clustering approach is then applied to infer the land-use types. The method is validated using mobile phone data collected in Singapore. Land use is determined with a detection rate of 58.03%. An analysis of the land-use classification results shows that the detection rate decreases as the heterogeneity of land use increases, and increases as the density of cell phone towers increases. 相似文献
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A reaction set of possible mineral weathering reactions is proposed to explain observed cation and silica export for the Emerald Lake watershed, a small Sierra Nevada, California catchment. The reaction set was calculated through a stoichiometric mole‐balance method, using a multiyear record of stream flow and snowpack chemical analyses and site‐specific mineral compositions. Reaction‐set calculations were intended to explore how the processes controlling stream cation and silica export depend on differing bedrock mineralogy across the catchment as snowmelt and runoff patterns change over the year. Different regions within the watershed can be differentiated by lake inflow subdrainages, each exhibiting different stream‐flow chemistry and calculated weathering stoichiometry, indicating that different silica and cation generation processes are dominant in wet steep portions of the catchment. Short‐term differences in stream concentrations were assumed to reflect ion exchange equilibria and rapid biological processes, whereas long‐term persistent stream concentration differences in different areas of the catchment were assumed to reflect spatial variability in mineral weathering stoichiometry. Mineralogical analyses of rock samples from the watershed provided site‐specific chemical compositions of major mineral species for reaction calculations. Reaction sets were evaluated by linear regression of calculated versus observed differences between snowmelt and stream‐flow chemistry and by a combined measure. Initially, single weathering reactions were balanced and evaluated to determine the reactions that best explained observed stream chemical export. Next, reactions were combined, using mineral compositions from different rock types to estimate the dependence of ion fluxes on lithology. The seasonal variability of major solute calculated fluxes is low, approximately one order of magnitude, relative to the observed three orders of magnitude variability in basin discharge. Reaction sets using basin‐averaged lithology and Aplite lithologies gave superior explanations of stream chemical composition. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
58.
B.A. Ridley H.I. Schiff A.W. Shaw L.R. Megill L. Bates C. Howlett H. Levaux T.E. Ashenfelter 《Planetary and Space Science》1974,22(1):19-24
On 16 March 1973, the York U./U.S.U. chemiluminescent nitric oxide instrument was flown successfully from Hollomon Air Force Base, New Mexico, 32° 50·1′ N lat. The instrument was operated between 17:40 and 22:05UT. Most of the measurements were carried out during three ascent, float and descent cycles between 17·4 and 22·9 km. Within the uncertainty of the measurements no differences were seen among results obtained during ascent, float and descent mode, which indicated that there were no major sampling problems resulting from contamination of the atmosphere. The NO mixing ratio was found to be 0·1 ppb v/v with an accuracy of 60 per cent. No change was observed within this accuracy over the small altitude range investigated. 相似文献
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This paper offers an exploratory investigation of the effects of a child's age on three behavioral constructs (awareness space, activity space, and attitude) concerning a downtown shopping center in Bristol, England. The data are elicited from three samples of Bristol school children defined according to age and are analyzed using statistical inferential procedures. The results disclose that awareness space and activity space consistently increase with age. In addition, attitudinal responses to specific features of the shopping center exhibit a gradual change over a long-term period. 相似文献