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971.
Anthony Astoul Christopher Filliter Eric Mason Andrew Rau-Chaplin Kunal Shridhar Blesson Varghese Naman Varshney 《Bulletin of Earthquake Engineering》2013,11(6):1973-2005
An automated, real-time, multiple sensor data source relying and globally applicable earthquake loss model and visualiser is desirable for post-event earthquake analysis. To achieve this there is a need to support rapid data ingestion, loss estimation and integration of data from multiple data sources and rapid visualisation at multiple geographic levels. In this paper, the design and development of the Automated Post-Event Earthquake Loss Estimation and Visualisation (APE-ELEV) system for real-time estimation and visualisation of insured losses incurred due to earthquakes is presented. A model for estimating ground up and net of facultative losses due to earthquakes in near real-time is implemented. Since post-event data is often available immediately from multiple disparate sources, a geo-browser is employed to facilitate the visualisation and integration of earthquake hazard, exposure and loss data. The feasibility of APE-ELEV is demonstrated using a test case earthquake that occurred in Tohoku, Japan (2011). The APE-ELEV model is further validated for ten global earthquakes using industry loss data. 相似文献
972.
Jung Eun Lim Mahtab Ahmad Sang Soo Lee Christopher L. Shope Yohey Hashimoto Kwon‐Rae Kim Adel R. A. Usman Jae E. Yang Yong Sik Ok 《洁净——土壤、空气、水》2013,41(12):1235-1241
Low cost lime‐based waste materials have recently been used to immobilize metals in contaminated soils. This study was conducted to evaluate the effects of oyster shells and eggshells as lime‐based waste materials on immobilization of cadmium (Cd) and lead (Pb) in contaminated soil, as well as their effects on metal availability to maize plants (Zea mays L.). Oyster shells and eggshells were applied to soils at 1 and 5% w/w, after which they were subject to 420 days of incubation. The toxicity characteristic leaching procedure (TCLP) test was employed to determine the mobility of Cd and Pb in soils. The results showed that the addition of waste materials effectively reduced the metal mobility as indicated by the decrease in the concentration of TCLP‐extractable Cd and Pb, and this was mainly due to significant increases in soil pH (from 6.74 in untreated soil to 7.85–8.13 in treated soil). A sequential extraction indicated that the addition of such alkaline wastes induced a significant decline in the concentration of Cd in the exchangeable fraction (from 23.64% in untreated soil to 1.90–3.81% in treated soil), but it increased the concentration of Cd in the carbonate fraction (from 19.59% in untreated soil to 36.66–46.36% in treated soil). In the case of Pb, the exchangeable fraction was also reduced (from 0.67% in untreated soil to 0.00–0.01% in treated soil), and the fraction of Pb bound to carbonate was slightly increased (from 16.61% in untreated soil to 16.41–18.25% in treated soil). Phytoavailability tests indicated that the metal concentrations in the shoots of maize plant were reduced by 63.39–77.29% for Cd and by 47.34–75.95% for Pb in the amended soils, with no significant differences being observed for the amendment types and the application rates. Overall, these results indicate that oyster shells and eggshells can be used as low cost lime‐based amendments for immobilizing Cd and Pb in contaminated soils. 相似文献
973.
974.
Hispanics are an internally diverse population, yet residential segregation within census-defined groups is often overlooked. Census data are used to examine evenness and exposure segregation among Hispanics in Chicago, Miami, and Phoenix along the lines of national origin, race, year of arrival, and income. Results suggest that segregation exists in Miami where there is more national origin diversity, between white and black Hispanics in Chicago, in all three cities for foreign-born Hispanic recent arrivals, and especially between high- and low-income Hispanics. Attempts to theorize immigration, social capital and solidarity, and the future of democratic society have inadequately conceptualized “diversity”; our work critically employs quantitative analysis to suggest an enriched and more nuanced socio-spatial understanding of the term. 相似文献
975.
Empirical evidence of environmental performance of urban areas designed according to the principles of sustainable urbanism is limited. Using the case study of Civano, a planned development that was designed and marketed as a sustainable community in Tucson, Arizona, we quantify fine-scale differences in urban form and delivery of ecosystem services. We found that the urban design of the first phase of development translated to the lowest surface temperatures and highest albedo and vegetative density. The first and second phases of the development greatly reduced potable water consumption through the addition of nonpotable resources; however, the second phase had higher temperatures and less dense vegetation than even the conventional development. Our results show modest improvements in environmental performance through sustainable urbanism and suggest further refinement in fine-scale spatial analysis of the role of urban design in the provisioning of services. 相似文献
976.
Christopher E. Brehme Patrice McCarron Heather Tetreault 《The Professional geographer》2013,65(1):98-109
As coastlines face increased development pressure, it is important to have the best available spatial information on coastal activities, including commercial fishing. This article describes the creation of a fine-scale spatial representation of lobster fishing activity along the Maine coast of the United States using a combination of participatory geographic information systems (GIS) and dasymetric mapping methods. These methods are employed here to support data collection from a large number of active lobster harvesters while maintaining individual privacy. The resulting representation of the fishery is designed as a planning tool for identifying potential interactions between marine resources and human activities. 相似文献
977.
AbstractWe have contrived a model E(αω) α μ?1ω?p+1(ω 2?ω i 2)?+ for the distribution of internal wave energy in horizontal wavenumber, frequency-space, with wavenumber α extending to some upper limit μ(ω) α ω r-1 (ω 2?ω i 2)½, and frequency ω extending from the inertial frequency ω i to the local Väisälä frequency n(y). The spectrum is portrayed as an equivalent continuum to which the modal structure (if it exists) is not vital. We assume horizontal isotropy, E(α, ω) = 2παE(α1, α2, ω), with α1, α2 designating components of α. Certain moments of E(α1, α2, ω) can be derived from observations. (i) Moored (or freely floating) devices measuring horizontal current u(t), vertical displacement η(t),…, yield the frequency spectra F (u,η,…)(ω) = ∫∫ (U 2, Z 2,…)E(α1, ∞2, ω) dα1 dα2, where U, Z,… are the appropriate wave functions. (ii) Similarly towed measurements give the wavenumber spectrum F (…)(α1) = ∫∫… dα2 dω. (iii) Moored measurements horizontally separated by X yield the coherence spectrum R(X, ω) which is related to the horizontal cosine transform ∫∫ E(α1, α2 ω) cos α1 Xdα1 dα1. (iv) Moored measurements vertically separated by Y yield R(Y, ω) and (v) towed measurements vertically separated yield R(Y, α1), and these are related to similar vertical Fourier transforms. Away from inertial frequencies, our model E(α, ω) α ω ?p-r for α ≦ μ ω ω r, yields F(ω) ∞ ω ?p, F(α1) ∞ α1 ?q, with q = (p + r ? 1)/r. The observed moored and towed spectra suggest p and q between 5/3 and 2, yielding r between 2/3 and 3/2, inconsistent with a value of r = 2 derived from Webster's measurements of moored vertical coherence. We ascribe Webster's result to the oceanic fine-structure. Our choice (p, q, r) = (2, 2, 1) is then not inconsistent with existing evidence. The spectrum is E(∞, ω) ∞ ω ?1(ω 2?ω i 2 ?1, and the α-bandwith μ ∞ (ω 2?ω i 2)+ is equivalent to about 20 modes. Finally, we consider the frequency-of-encounter spectra F([sgrave]) at any towing speed S, approaching F(ω) as S ≦ S o, and F(α1) for α1 = [sgrave]/S as S ≧ S o, where S o = 0(1 km/h) is the relevant Doppler velocity scale. 相似文献
978.
Tenley M. Conway Christopher C. Wellen 《International journal of geographical information science》2013,27(10):1613-1631
Biogeographers have developed a new generation of statistical models called presence-only models, which require no data concerning the absence of a species and do not assume that the absence of a species indicates habitat unsuitability. Both characteristics are especially useful when modeling a species that is actively spreading across a landscape. Although urban expansion is sometimes equated to an invading species, the applicability of presence-only models has not yet been explored when modeling urban growth. This article compares predictions of urban growth using a presence-only model (ecological niche factor analysis) and a more traditional presence–absence model (logistic regression). An additional model used pseudo-absence sites, from the presence-only model output, as input into the presence–absence model. The models were applied to New Jersey's Barnegat Bay Watershed. Overall, the traditional presence–absence model performed the best, although the presence-only model was sufficiently similar to warrant further exploration of presence-only models when no reliable absence data (i.e., locations where no conversion occurred) exists. However, due to data-formatting requirements of the presence-only model, it is difficult to accommodate data pertaining to administrative boundaries, which are inherently Boolean. Finally, the output based on the pseudo-absence approach overpredicted urban conversion when compared to the other approaches. 相似文献
979.
Christopher J. Amante 《International journal of geographical information science》2013,27(11):2188-2217
ABSTRACTFuture sea-level rise will likely expand the inland extent of storm surge inundation and, in turn, increase the vulnerability of the people, properties and economies of coastal communities. Modeling future storm surge inundation enhanced by sea-level rise uses numerous data sources with inherent uncertainties. There is uncertainty in (1) hydrodynamic storm surge models, (2) future sea-level rise projections, and (3) topographic digital elevation models representing the height of the coastal land surface. This study implemented a Monte Carlo approach to incorporate the uncertainties of these data sources and model the future 1% flood zone extent in the Tottenville neighborhood of New York City (NYC) in a probabilistic, geographical information science (GIS) framework. Generated spatiotemporal statistical products indicate a range of possible future flood zone extents that results from the uncertainties of the data sources and from the terrain itself. Small changes in the modeled land and water heights within the estimated uncertainties of the data sources results in larger uncertainty in the future flood zone extent in low-lying areas with smaller terrain slope. An interactive web map, UncertainSeas.com, visualizes these statistical products and can inform coastal management policies to reduce the vulnerability of Tottenville, NYC to future coastal inundation. 相似文献
980.
Joachim W. Stock Christopher S. Boxe Ralph Lehmann J. Lee Grenfell A. Beate C. Patzer Heike Rauer Yuk L. Yung 《Icarus》2012,219(1):13-24
The chemical composition of a planetary atmosphere plays an important role for atmospheric structure, stability, and evolution. Potentially complex interactions between chemical species do not often allow for an easy understanding of the underlying chemical mechanisms governing the atmospheric composition. In particular, trace species can affect the abundance of major species by acting in catalytic cycles. On Mars, such cycles even control the abundance of its main atmospheric constituent CO2. The identification of catalytic cycles (or more generally chemical pathways) by hand is quite demanding. Hence, the application of computer algorithms is beneficial in order to analyze complex chemical reaction networks. Here, we have performed the first automated quantified chemical pathways analysis of the Martian atmosphere with respect to CO2-production in a given reaction system. For this, we applied the Pathway Analysis Program (PAP) to output data from the Caltech/JPL photochemical Mars model. All dominant chemical pathways directly related to the global CO2-production have been quantified as a function of height up to 86 km. We quantitatively show that CO2-production is dominated by chemical pathways involving HOx and Ox. In addition, we find that NOx in combination with HOx and Ox exhibits a non-negligible contribution to CO2-production, especially in Mars’ lower atmosphere. This study reveals that only a small number of chemical pathways contribute significantly to the atmospheric abundance of CO2 on Mars; their contributions to CO2-production vary considerably with altitude. This analysis also endorses the importance of transport processes in governing CO2-stability in the Martian atmosphere. Lastly, we identify a previously unknown chemical pathway involving HOx, Ox, and HO2-photodissociation, contributing 8% towards global CO2-production by chemical pathways using recommended up-to-date values for reaction rate coefficients. 相似文献