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71.
Casey R. Lynch 《Urban geography》2013,34(8):1148-1167
Increasingly over the past few years the building of new cities “from scratch” has become a key strategy to promote development across much of the Global South. While several projects are currently under construction, many others exist primarily as proposals awaiting adequate investment or government action. This paper builds on previous literature that considers representations of such projects – promotional materials, digitally-produced video simulations, and master plans – as key components in the production of imagined urban futures. Through an exploration of the proposed Zone for Economic Development and Employment (ZEDE) in Honduras, this article demonstrates a feminist geopolitical approach focused on how such representations of utopian urbanism circulate through the local communities slated for new city development. I examine how representations of future urban spaces and future urban governance regimes become appropriated by local residents in organizing opposition or otherwise making sense of the proposed project’s potential impact on their lives. 相似文献
72.
Two-dimensional Lagrangian trajectories are studied near an idealized ocean front with shear and convergence plus an uncorrelated random walk. Applications include fixed-depth drifters and plankton patches with perfect depth regulation. 相似文献
73.
M. T. Rushton B. Kaminsky D. K. Lynch † Ya. V. Pavlenko A. Evans S. P. S. Eyres C. E. Woodward † Ray W. Russell † Richard J. Rudy † Michael L. Sitko † T. Kerr 《Monthly notices of the Royal Astronomical Society》2010,401(1):99-104
We present near-infrared spectroscopy of the recurrent nova RS Ophiuchi (RS Oph) obtained on several occasions after its latest outburst in 2006 February. The 1–5 μ m spectra are dominated by the red giant, but the H i , He i and coronal lines present during the eruption are present in all our observations. From the fits of the computed infrared spectral energy distributions to the observed fluxes, we find T eff = 4200 ± 200 K for the red giant. The first overtone CO bands at 2.3 μ m, formed in the atmosphere of the red giant, are variable. The spectra clearly exhibit an infrared excess due to dust emission longward of 5 μ m; we estimate an effective temperature for the emitting dust shell of 500 K, and find that the dust emission is also variable, being beyond the limit of detection in 2007. Most likely, the secondary star in RS Oph is intrinsically variable. 相似文献
74.
Thomas F. Lynch 《Quaternary Research》1974,4(3):356-377
The initial peopling of South America is reviewed in terms of geochronological and archaeological data. The problem is put in historical perspective and a systematic evaluation is made of the latest typologically oriented arguments for the presence of preprojectile point complexes. Field evidence is very weak for early Biface and Chopper traditions. There is better support for an early Flake tradition, but it is not likely to precede the use of stone projectile points.Radiocarbon dates and “terrace dating” should be used only with great caution and careful attention to the nature of cultural and stratigraphic associations. Uncritical acceptance of determinations on bone and soil samples has led to extremely problematic cultural reconstructions. Emphasis on stratified sites with finished artifacts, faunal assocations, and charcoal dates leads to a reconstruction at odds with those presented in recent textbooks. It is concluded that the bulk of solid evidence favors the entry of man as a big game hunter using stone projectile points and having an adaptation much like that of the Paleo-Indians of North America. 相似文献
75.
Classification tests have been carried out on limestone in 10.2-, 15.2-, 25.4- and 38.1-cm “Krebs” hydrocyclones in order to study the effect of cyclone diameter on the reduced-efficiency curve. Parameters which were varied included the vortex finder and spigot diameter, throughput and feed-solids content, but the feed size remained constant. The reduced-efficiency curve was found to be constant for all tests and the conclusion is that for constant feed size this curve is a function of the material being classified only for geometrically similar cyclones and is independent of the cyclone diameter. 相似文献
76.
David K. Lynch Richard J. Rudy Ray W. Russell Carl J. Rice Stephan Mazuk Catherine Venturini Richard C. Puetter Michael L. Sitko Roc Cutri 《Astrophysics and Space Science》2002,279(1-2):57-64
IR spectroscopy and photometry in the 0.8–2.4 and 3–14 mregions are reported for seven dates between March 21 1998 and July20 2000 UT. The shorter wavelength region displays a smooth continuum increasing to longerwavelengths that is indicative of the Wien tail of a Planck function. Only theHe I 1.0830 line is present early and it shows a P-Cygni profile which laterdisappears. The long wave spectra show a smooth continuum between 3 and 13m that was well fit by a gray body at 1000 K. A weak, unidentifiedemission feature appears between 8 and 10 m. 相似文献
77.
An assessment of the influence of land cover uncertainties on the simulation of global climate in the early Holocene 总被引:1,自引:0,他引:1
Six and 21 kyear BP represent the extreme states of climate since the last glacial maximum. The early Holocene, in contrast, was a time of transition, experiencing rapidly melting continental ice sheets, rising sea-level, and increasing summer insolation. Key features of the climate, illustrated by an NCAR CCM3 general circulation model experiment representing 11 kyr BP, include enhanced continentality and seasonality, and an enhanced northern monsoon. The principal circulation responses to the 11 kyr BP boundary conditions can be summarized as an intensification and northward shift of the mean meridional circulation and an intensification of the planetary wave structure of the Northern Hemisphere in northern summer, and a slight intensification of the mean meridional circulation coupled with a southward shift in the planetary wave structure in northern winter. These changes are manifest in the enhancement of the typical seasonal cycle of sea-level pressure in the Northern Hemisphere relative to that of the present day, and enhancement and equatorward shift of the Aleutian and Icelandic lows in northern winter. Over the period 15-8 kyr BP, within the current boreal forest zone, herbaceous tundra was replaced by shrub tundra, and subsequently by evergreen or deciduous forest, but there is uncertainty in the location, timing, and exact nature of these transitions. The specific location of the relatively small area of the Asian boreal forest-tundra transition can have an impact on regional climate, primarily in the net shortwave radiation component of the surface energy budget in spring, and in the cloudiness, net shortwave radiation, and turbulent heat fluxes in summer. These changes also have an impact on global climate. Our results suggest that the additional northern heating leads to a reduced equator-pole heat transport in the Northern Hemisphere which then influences heat and momentum transport in the Southern Hemisphere. 相似文献
78.
Long-term impacts of forest treatments on water yield: a summary for northeastern USA 总被引:9,自引:0,他引:9
J.W. Hornbeck M.B. Adams E.S. Corbett E.S. Verry J.A. Lynch 《Journal of Hydrology》1993,150(2-4):323-344
Long-term changes in annual water yield are summarized and compared for 11 catchment studies in the northeastern USA. Substantial increases in water yield of up to 350 mm year−1 were obtained in the first year by clearing forest vegetation and controlling regrowth with herbicides. Commercial clearcutting with natural regrowth resulted in initial increases in water yield of 110–250 mm year−1. This range in response was due to differences in precipitation and configuration of cuttings. Unless regrowth was controlled with herbicides, yield increases declined quickly after cutting, seldom persisting for more than 10 years. However, yield increases were readily extended over 20 years or more with intermediate cuttings and/or repeated control of regrowth with herbicides. Nearly all increases in water yield occur during the growing season as augmentation of baseflow. Changes in species composition after forest cutting on several study catchments eventually resulted in decreased water yields compared with those from uncut, control catchments. Results are discussed in terms of implications for surface water supplies, global climate change, nutrient cycling, hydrological modeling, and long-term research. 相似文献
79.
Centrifuge tests were carried out to determine the effect of different alcohols and one glycol on a thin consolidated disc
of clay. The evolution of changes in the clay hydraulic conductivity with time was investigated and other structural changes
due to chemical attack were monitored. The findings presented here demonstrate that the hydraulic conductivity of the clay
appear to be generally related to the polarity of the chemicals and the dielectric constant, with the exception of butanol.
In the case of butanol at low flow rate and low stress level, the action of the chemical caused the clay to crack, with a
consequent large increase in flow. This effect on the clay hydraulic conductivity could be used for improving pollution remediation
especially when alcohols are associated with gasoline. 相似文献
80.
The Coulter Multisizer has clearly defined strengths and weaknesses as a particle-sizing instrument. It is easier to operate than its Coulter predecessors, though less so than several of its competitors. The Multisizer is best suited to handle very small samples with a narrow particle-size range, such as aeolian dusts and other sediments available only in small quantities. For such samples, Multisizer analysis times are short, resolution is very high (256 size classes) and reproducibility is good. The Multisizer is less well suited to soils and other samples available in large quantities and with a broad particle-size range. For soil particle-size analyses a composite method is proposed involving: Multisizer (2–75 μm), Pipette (<2 μm) and Sieve (>75 μm). © 1997 John Wiley & Sons, Ltd. 相似文献