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911.
Sok Kuh Kang Kyung Tae Jung Ki-Dai Yum Kwang-Soo Lee Jin-Soon Park Eun Jin Kim 《Ocean Science Journal》2012,47(4):453-463
Uldolmok waterway, located between an island off the southwestern tip of Korean peninsula and mainland, is famous for its strong tidal current that has a maximum current of about 6.0m/s. A series of field observations along with numerical modeling have been carried out in order to understand the tidal dynamics in terms of the force balance along the whole waterway and the energy balance in the narrowest part of the waterway. First, analysis of the ADCP current and the tide level variation data reveals that the tidal dynamics along the total waterway (channel) is balanced dominantly between the pressure gradient and linear bottom frictional forces, with the phase lag of sea level difference for the semi-diurnal constituents leading the current phase about by 10°. Secondly, the result of the numerical modeling reveals that the tidal energy flux vector flows toward the narrowest section, indicating that there should be related nonlinear processes. Through the numerical model experiment with multi-components, the convergence of (M2 + S2) tidal energy flux of 6.68 × 107 Joule/s in the narrow area of the Uldolmok waterway is explained mainly by the energy consumption of 73% through the nonlinear generation of shallow water components and by the bottom frictional energy dissipation of 27%. This reveals that the remarkably strong nonlinear process dominates in the narrowest section of the Uldolmok waterway, compared with other areas, such as Yellow and East China Seas where the total M2 energy flux through the open boundary is balanced in terms of the bottom dissipation (Kang et al. 2003; Choi 1980). 相似文献
912.
Tintinnid species as biological indicators for monitoring intrusion of the warm oceanic waters into Korean coastal waters 总被引:2,自引:0,他引:2
Young-Ok Kim Kyoungsoon Shin Pung-Guk Jang Hyun-Woo Choi Jae-Hoon Noh Eun-Jin Yang Eung Kim Dongchull Jeon 《Ocean Science Journal》2012,47(3):161-172
This study examined seasonal and annual occurrences of warm oceanic tintinnid species in southern Korea coastal waters. The indicative species of tintinnids was monitored using three approaches: monitoring from cruises traveling from the warm pool in the western North Pacific to the Korea Strait; biweekly or monthly monitoring in the Korea Strait; and daily monitoring in the nearshore water. Annual pulses of warm oceanic indicator species were regularly observed in the Korea Strait. In September 2008 recorded a maximum species number of warm water indicators, a representative species for warm oceanic waters, Climacocylis scalaroides was simultaneously detected in the nearshore water as well as the Korea Strait. The result indicates that the greater warm water extension into Korean coastal areas was in September 2008. Sharp declines in species diversity were observed in the transitional area between neritic and Kuroshio zone in East China Sea (ECS). Epiplocyloides reticulata, reported previously as a Kuroshio indicator, was considered an ECS indicator species, as it was undetected in the western North Pacific central zone but was found abundantly in the ECS. Tintinnid species can be used as biological indicators to detect the inflow of warm oceanic waters into Korean coastal waters. 相似文献
913.
Kyung-Il Park Ludovic Donaghy Hyun-Sil Kang Hyun-Ki Hong Young-Ok Kim Kwang-Sik Choi 《Ocean Science Journal》2012,47(1):19-26
Cellular and humoral immune parameters are often used as biomarkers to trace environmental and physiological stresses in marine
bivalves. In this study, we compared various immune parameters of Manila clams (Ruditapes philippinarum) under normal conditions and under a high level of desiccation, using flow cytometry. The immune parameters analyzed included,
total hemocyte count, hemocyte mortality, hemocyte DNA damage, reactive oxygen species (ROS) production, and phagocytosis
activity. Total hemocyte count, hemocyte DNA damage, and hemocyte mortality were significantly elevated among clams under
high desiccation stress, while phagocytosis activity and spontaneous ROS production were significantly lower compared to those
parameters of the control clams (p<0.05). These data suggest that the immune parameters analyzed in this study well reflect the physiological status of clams. 相似文献
914.
915.
This paper reviews the theoretical principles of subspace system identification as applied to the problem of estimating black‐box state‐space models of support‐excited structures (e.g., structures exposed to earthquakes). The work distinguishes itself from past studies by providing readers with a powerful geometric interpretation of subspace operations that relates directly to theoretical structural dynamics. To validate the performance of subspace system identification, a series of experiments are conducted on a multistory steel frame structure exposed to moderate seismic ground motions; structural response data is used off‐line to estimate black‐box state‐space models. Ground motions and structural response measurements are used by the subspace system identification method to derive a complete input–output state‐space model of the steel frame system. The modal parameters of the structure are extracted from the estimated input–output state‐space model. With the use of only structural response data, output‐only state‐space models of the system are also estimated by subspace system identification. The paper concludes with a comparison study of the modal parameters extracted from the input–output and output‐only state‐space models in order to quantify the uncertainties present in modal parameters extracted from output‐only models. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
916.
Young-Rae Kim Rupert A. C. Croft 《Monthly notices of the Royal Astronomical Society》2008,387(1):377-386
Using cosmological hydrodynamic simulations, we measure the mean transmitted flux in the Lyα forest for quasar sightlines that pass near a foreground quasar. We find that the trend of absorption with pixel quasar separation distance can be fitted using a simple power-law form including the usual correlation function parameters r 0 and γ, so that . From the simulations, we find the relation between r 0 and quasar host mass, and formulate this as a way to estimate quasar host dark matter halo masses, quantifying uncertainties due to cosmological and IGM parameters, and redshift errors. With this method, we examine data for ∼9000 quasars from the Sloan Digital Sky Survey (SDSS) Data Release 5, assuming that the effect of ionizing radiation from quasars (the so-called transverse proximity effect) is unimportant (no evidence for it is seen in the data). We find that the best-fitting host halo mass for SDSS quasars with mean redshift z = 3 and absolute G -band magnitude −27.5 is log M /M⊙ = 12.68+0.81 −0.67 . We also use the Lyman-Break Galaxy (LBG) and Lyα forest data of Adelberger et al. in a similar fashion to constrain the halo mass of LBGs to be log10 M /M⊙ = 11.41+0.54 −0.59 , a factor of ∼20 lower than the bright quasars. In addition, we study the redshift distortions of the Lyα forest around quasars, using the simulations. We use the quadrupole to monopole ratio of the quasar Lyα forest correlation function as a measure of the squashing effect. We find its dependence on halo mass difficult to measure, but find that it may be useful for constraining cosmic geometry. 相似文献
917.
G. W. Wilson J. E. Austermann T. A. Perera K. S. Scott P. A. R. Ade J. J. Bock J. Glenn S. R. Golwala S. Kim Y. Kang D. Lydon P. D. Mauskopf C. R. Predmore C. M. Roberts K. Souccar M. S. Yun 《Monthly notices of the Royal Astronomical Society》2008,386(2):807-818
AzTEC is a mm-wavelength bolometric camera utilizing 144 silicon nitride micromesh detectors. Here, we describe the AzTEC instrument architecture and its use as an astronomical instrument. We report on several performance metrics measured during a three-month observing campaign at the James Clerk Maxwell Telescope and conclude with our plans for AzTEC as a facility instrument on the Large Millimetre Telescope. 相似文献
918.
Min S. Yun Itziar Aretxaga Matthew L. N. Ashby Jason Austermann Giovanni G. Fazio Mauro Giavalisco Jia–Sheng Huang David H. Hughes Sungeun Kim James D. Lowenthal Thushara Perera Kim Scott Grant Wilson Joshua D. Younger 《Monthly notices of the Royal Astronomical Society》2008,389(1):333-340
High-redshift submillimetre-bright galaxies identified by blank field surveys at millimetre and submillimetre wavelengths appear in the region of the Infra Red Array Camera (IRAC) colour–colour diagrams previously identified as the domain of luminous active galactic nuclei (AGNs). Our analysis using a set of empirical and theoretical dusty starburst spectral energy distribution (SED) models shows that power-law continuum sources associated with hot dust heated by young (≲100 Myr old), extreme starbursts at z > 2 also occupy the same general area as AGNs in the IRAC colour–colour plots. A detailed comparison of the IRAC colours and SEDs demonstrates that the two populations are distinct from each other, with submillimetre-bright galaxies having a systematically flatter IRAC spectrum (≳1 mag bluer in the observed [4.5]–[8.0] colour). Only about 20 per cent of the objects overlap in the colour–colour plots, and this low fraction suggests that submillimetre galaxies powered by a dust-obscured AGN are not common. The red infrared colours of the submillimetre galaxies are distinct from those of the ubiquitous foreground IRAC sources, and we propose a set of infrared colour selection criteria for identifying SMG counterparts that can be used even in the absence of radio or Multiband Imaging Photometer for Spitzer (MIPS) 24 μm data. 相似文献
919.
V. F. Gopka A. V. Yushchenko V. A. Yushchenko I. V. Panov Ch. Kim 《Kinematics and Physics of Celestial Bodies》2008,24(2):89-98
Absorption lines of some actinides, namely, actinium (Z = 89), protactinium (91), neptunium (93), plutonium (94), americium (95), curium (96), berkelium (97), californium (98), and einsteinium (99), were identified in the spectrum of one of the most peculiar main-sequence stars HD 101065 (Przybylski’s star). In the identification we used a high-resolution spectrum (R = 80 000) acquired at the 8.2-m ESO telescope. 相似文献
920.
The chemical and biological characteristics of surface waters in Jinhae Bay were investigated over four seasons to understand water quality in light of the growing industrialisation occurring within this area. Jinhae Bay includes four smaller bays: Masan; Hangam; Jindong; and Gohyun. The water quality in Jinhae Bay varied spatially and seasonally. The water quality of both Hangam Bay and Masan Bay was highly degraded, demonstrating high concentrations of ammonia, nitrate, chlorophyll a and particulate organic carbon. Contamination from sewage was the dominant cause of the water quality deterioration in these bays. Conversely, the water quality in Jindong Bay and Gohyun Bay was not as severely affected as that of the above two bays. Water quality in Jinhae Bay was particularly poor in summer when nutrient loading was highest due to the run-off associated with high precipitation. Principal component analysis indicated that nitrogen contamination was a major factor influencing the water quality of Jinhae Bay. The effective reduction in high-nitrogen discharges is essential to improve water quality in Jinghae Bay. 相似文献