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The World Coordinate System (WCS) is a standard for embedding coordinate information in a Flexible Image Transport System
(FITS) header. Its first extensive use within solar physics is by the Sun Earth Connections Coronal and Heliospheric Investigation (SECCHI) telescope suite onboard the Solar Terrestrial Relations Observatory (STEREO). The WCS formalism assists in SECCHI data analysis in several ways: First of all, the spherical effects associated
with the extremely wide fields-of-view of the Heliospheric Imager (HI) telescopes can be handled in a completely unambiguous and standard fashion. Of particular importance is that WCS positional
keywords allow spacecraft-ephemeris information to be embedded within the FITS header without depending on mission-specific
keywords. Ephemeris data is critical to the three-dimensional analysis that the STEREO mission is designed for. We also show
how the WCS software in
SolarSoft\textsf{SolarSoft}
can be used to relate STEREO data to other missions such as the Solar and Heliospheric Observatory (SOHO). The ability of WCS to support a parallel celestial right ascension (R.A.)/declination (Dec) coordinate system and
the use of WCS for COR1 synoptic maps are also discussed. The advantages that STEREO derived from WCS can equally be applied
to other solar missions, in particular Solar Orbiter, and should be adopted by all future missions. 相似文献
96.
Jonathan J. Liberda Jeroen W. Thompson W. Jack Rink Federico Bernaldo de Quirs Rohit Jayaraman Kailash Selvaretinam Kerry Chancellor‐Maddison Vito Volterra 《Geoarchaeology》2010,25(4):467-474
Nine faunal teeth from layer 20 of El Castillo cave in Cantabrian Spain were dated using electron spin resonance (ESR). Two teeth were rejected due to inconsistent subsample ages, while the remaining teeth yielded a mean age that is consistent with the stratigraphic expectations: 42.7±3.5. Uncertainty in the external γ dose rate results in a potential systematic uncertainty of±6.4ka that should affect all samples equally. The results provide independent confirmation of previously reported 14C ages for layer 20. © 2010 Wiley Periodicals, Inc. 相似文献
97.
Patricia Carbajales-Dale Dusti Annan-Coultas Anjali Joseph Martie Thompson Roxana Jafarifiroozabadi Susan P. Limber Bonnie Holaday Sahar Mihandoust 《Transactions in GIS》2023,27(4):975-995
Geographic information systems (GIS) have become essential tools in the public health domain, especially when it comes to monitoring and surveillance of disease. The purpose of this article is to describe and explore the benefits of using GIS to improve public health emergency response during a global pandemic and, in particular, how to effectively optimize the allocation of public health resources in a rural setting using a data-driven approach that considers the multifactorial demand for new COVID-19 testing sites. Herein, the authors present their interprofessional project as an example of such efforts to inform applications for practice. The team developed a GIS-based multicriteria decision analysis model for use by decision-makers and public health experts in similar future planning and response scenarios. Focus is placed on rural characteristics (e.g., accessibility), vulnerable populations, and daily changing conditions (e.g., COVID-19 daily case fluctuations) that create additional challenges for public health agencies and policymakers. 相似文献
98.
Observational estimate of climate sensitivity from changes in the rate of ocean heat uptake and comparison to CMIP5 models 总被引:1,自引:0,他引:1
Troy Masters 《Climate Dynamics》2014,42(7-8):2173-2181
Climate sensitivity is estimated based on 0–2,000 m ocean heat content and surface temperature observations from the second half of the 20th century and first decade of the 21st century, using a simple energy balance model and the change in the rate of ocean heat uptake to determine the radiative restoration strength over this time period. The relationship between this 30–50 year radiative restoration strength and longer term effective sensitivity is investigated using an ensemble of 32 model configurations from the Coupled Model Intercomparison Project phase 5 (CMIP5), suggesting a strong correlation between the two. The mean radiative restoration strength over this period for the CMIP5 members examined is 1.16 Wm?2K?1, compared to 2.05 Wm?2K?1 from the observations. This suggests that temperature in these CMIP5 models may be too sensitive to perturbations in radiative forcing, although this depends on the actual magnitude of the anthropogenic aerosol forcing in the modern period. The potential change in the radiative restoration strength over longer timescales is also considered, resulting in a likely (67 %) range of 1.5–2.9 K for equilibrium climate sensitivity, and a 90 % confidence interval of 1.2–5.1 K. 相似文献
99.
Robert W. Thompson Andrew G. Dickson Samuel E. Kahng Christopher D. Winn 《Aquatic Geochemistry》2014,20(5):467-481
Inorganic carbon measurements made in the late 1980s suggest that alkalinity in the waters surrounding the Hawaiian Archipelago is elevated relative to the oligotrophic waters of the North Pacific. These observations have been interpreted as evidence for a “halo” of elevated carbonate saturation state produced by the dissolution of highly soluble magnesium calcites and aragonite on the island platform or in the water column surrounding the islands. If present, this “halo” has implications for air–sea carbon dioxide exchange in Hawaiian waters and may impact the response of coral reef communities to the acidification of the surface waters of the global ocean. The purpose of this study was to assess the magnitude and extent of the elevated calcium carbonate saturation state observed on previous expeditions to this region. Transects were conducted near several atolls in the Northwestern Hawaiian Islands from shallow water adjacent to the forereef to the open ocean 15 km from the island. Hydrographic profiles were collected at each station, and discrete water samples were collected for the measurement of carbon system parameters necessary to compute calcium carbonate saturation state. Our data were compared with observations made at the Hawaii Ocean Time-series site at Station ALOHA and with hydrographic data collected on the WOCE lines in the North Pacific around the archipelago. We did not detect a carbonate dissolution halo around the islands. We conclude that the previously observed halo was probably an analytical artifact, or possibly a result of extreme variability in carbon chemistry surrounding the islands. 相似文献
100.
Rock reinforcement is widely used in tunnels and surface and underground mines. A large number of proprietary products are available in various configurations of components. While the mechanical properties of the primary element are available from product brochures, the associated component properties may vary widely and adversely influence the overall performance of the system. Field pull out tests are most commonly used to measure the system response in the toe anchor region. However, the response of the collar region is less commonly considered but may be more important. Several case studies are described in which various components and systems of rock bolts and cable bolts have been subjected to static loading in the laboratory and in the field. The results generally demonstrate the importance of considering the properties of all the components and not simply those of the primary element. In some cases, the internal fixtures have strengths much less than the elements. Often it has also been found that the fixture at the collar has significantly less strength than the element and this will result in complete loss of function in restraining surface support hardware, such as plates, mesh and reinforced shotcrete. 相似文献