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511.
Mike Taylor 《New Zealand geographer》2013,69(2):158-166
This article focuses on the representation of disaster vulnerability, using the 2010 Haiti earthquake to problematise recent changes in secondary school curriculum and assessment. Drawing upon media perspectives of the Haiti earthquake, the article contrasts a traditional and relational teaching approach to the concept of disaster vulnerability. The article concludes that teachers need to draw upon a wider range of geographical paradigms in order to move students towards critical engagement with societal issues, a key aim of the social science learning area in the New Zealand Curriculum. 相似文献
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Jeffrey Turner Hans‐Jrgen Albrechtsen Mike Bonell Jean‐Pierre Duguet Bob Harris Rainer Meckenstock Kevin McGuire Roger Moussa Norman Peters Hans H. Richnow Barbara Sherwood‐Lollar Stefan Uhlenbrook Henny van Lanen 《水文研究》2006,20(1):205-213
A summary is provided of the first of a series of proposed Integrated Science Initiative workshops supported by the UNESCO International Hydrological Programme. The workshop brought together hydrologists, environmental chemists, microbiologists, stable isotope specialists and natural resource managers with the purpose of communicating new ideas on ways to assess microbial degradation processes and reactive transport at catchment scales. The focus was on diffuse contamination at catchment scales and the application of compound‐specific isotope analysis (CSIA) in the assessment of biological degradation processes of agrochemicals. Major outcomes were identifying the linkage between water residence time distribution and rates of contaminant degradation, identifying the need for better information on compound specific microbial degradation isotope fractionation factors and the potential of CSIA in identifying key degradative processes. In the natural resource management context, a framework was developed where CSIA techniques were identified as practically unique in their capacity to serve as distributed integrating indicators of process across a range of scales (micro to diffuse) of relevance to the problem of diffuse pollution assessment. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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A COMPARISON OF EASTERN AND WESTERN HONG KONG PHYTOPLANKTON FROM WEEKLY SAMPLES (1997-1999) 总被引:3,自引:0,他引:3
Weekly phytoplankton samples were taken from western Hong Kong (Lamma) from Jan. 1997 to Dec. 1999 and from Port Shelter in
Eastern Hong Kong from January 1998 to December 1999. During that time diatom blooms occurred repeatedly at both sites but
never in synchrony. One species would bloom at one site and then weeks later it or another species would bloom at the other
site; while the 1998 red tide of the mucus producing dinoflagellateGymnodinium mikimotoi occurred at both sites. It first occurred at the Port Shelter site in March and did not appear at the Lamma site until April.
With the single exception of this species, no other dinoflagellate reached bloom concentrations at the Lamma site. In addition,
dinoflagellate abundance at the Lamma site was significantly lower (P<0.05) than that at the Port Shelter site. This was correlated
with a significantly higher turbidity (i. e. low Secchi transparency) and higher turbulence (stronger currents) at the Lamma
site.
Annual variation in surface temperature correlated with total surface phytoplankton abundance at both our sample sites. Phytoplankton
abundance increased in spring as water temperatures warmed. In fall, as surface water temperatures began to decline and the
monsoon rains became less frequent there was a reduction in phytoplankton abundance associated with the reduction in temperature
and light. Because so many variables co-occur with temperature (e. g. the amount of rainfall light intensity and light duration
etc.) it is not possible to cite temperature as the causal factor associated weth controlling phytoplankton abundance at our
two sample sites.
Our data support the rather controversial notion that percentage-wise, there are relatively more harmful bloom forming species
in nutrient-rich coastal waters than there are in the world's oceans. 16% of the dinoflagellate species and 10.3% of the diatom
species observed at our two sample sites were classed as harmful. These percentages were higher than those cited by Sournia
(1995) for the worlds oceans (9.6% and 6.8% respectively). This raises the possibility that there are relatively more toxic
species in the nutrient-rich coastal waters of the world than there are in the mid ocean nutrient-poor areas of the world.
Some reasons for this are briefly discussed. 相似文献
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A new use for a 2-dimensional position sensitive diode (PSD) is described. A duolateral PSD was used with a microchannel plate
image intensifier as a proof-of-concept photon counting (event driven) imager for astronomical imaging and photometry. This
produced an imager capable of counting 25–30 kcps over the astronomical bands B, V & R, with an overall efficiency of ∼19%. 相似文献
520.
The Hyde-Macraes Shear Zone (HMSZ) is a regionally continuous, low-angle, NE dipping (~15°) late-metamorphic thrust zone in
the Mesozoic Otago Schist. The shear zone, which is host to large volumes of mineralised schist, consists of foliated fissile
schist with some massive schist pods. Two sets of quartz veins are found within the HMSZ: thrust-related, shallowly dipping
veins that were emplaced parallel or sub-parallel to the shears and swarms of steeply dipping extensional veins, which cut
across the metamorphic foliation. The latter are restricted to the massive schist pods. Mutual cross-cutting relationships
occur between steep extensional veins and shallow-dipping veins, suggesting that they formed contemporaneously. The co-existence
of these two vein types locally implies local rotation of the principal stress axes to produce extensional veins within a
regional thrust setting. The steep extensional veins are spatially related to lateral and oblique ramps within the HMSZ. Three-dimensional
mechanical models show that these lateral or oblique ramps can produce favourable conditions for extensional vein formation
when combined with a high fluid pressure and oblique convergence. Mechanical requirements include a reduced differential stress,
a positive volumetric strain and an increase in the horizontal shear stress. Our models show that under certain conditions,
it is possible for extension-related structures to form during shortening because of local changes in the stress state without
the need for a regional scale switch in the imposed stress field. The convergence direction across the HMSZ during formation
of the steep extensional veins was ~WNW. 相似文献