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201.
Countries can use both mitigation and adaptation strategies to protect their citizens from catastrophic risk posed by climate
change (e.g., shift in the jet stream). A nation can mitigate by reducing CO2 emissions, which reduces the probability of a catastrophic event; it can adapt by altering the infrastructure so that damages
can be reduced in the event a catastrophe is realized. Herein we add to the current literature by extending the endogenous
risk framework into a dynamic framework permitting analysis of both mitigation and adaptation while allowing for the dynamic
process of global climate change. Our results suggest adaptation to catastrophe is a small fraction of the national climate
protection budget relative to mitigation when nations cooperate fully, when damages are both continuous and catastrophic,
and when nations have a short planning horizon. Adaptation becomes more important relative to mitigation when nations are
unlikely to cooperate, when damages are mainly catastrophic, or when the nation’s planning horizon increases. 相似文献
202.
Weller J 《The Astrophysical journal》1999,527(1):L1-L4
In a universe with inhomogeneous reionization, the ionized patches create a second-order signal in the cosmic microwave background polarization anisotropy. This signal originates in the coupling of the free-electron fluctuation to the quadruple moment of the temperature anisotropy. We examine the contribution from a simple inhomogeneous reionization model and find that the signal from such a process is below the detectable limits of the Planck Surveyor mission. However, the signal is above the fundamental uncertainty limit from cosmic variance, so that a future detection with a high-accuracy experiment on subarcminute scales is possible. 相似文献
203.
Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network,
vol. 34, no. 10, October 2009 (on the Internet at ). Edited by scientists at the Smithsonian, this bulletin includes reports provided by a worldwide network of correspondents.
The reports contain the names and contact information for all sources. Please note that these reports are preliminary and
subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism,
seismic unrest, monitoring data, and field observations. 相似文献
204.
205.
Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network,
vol. 33, no. 1, January 2008 (on the Internet at ). Edited by scientists at the Smithsonian, this bulletin includes reports provided by a worldwide network of correspondents.
The reports contain the names and contact information for all sources. Please note that these reports are preliminary and
subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism,
seismic unrest, monitoring data, and field observations. 相似文献
206.
Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network,
vol. 32, no. 11, November 2007 (on the Internet at ). Edited by scientists at the Smithsonian, this bulletin includes reports provided by a worldwide network of correspondents.
The reports contain the names and contact information for all sources. Please note that these reports are preliminary and
subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism,
seismic unrest, monitoring data, and field observations. 相似文献
207.
Information included in this summary is based on more detailed reports published in the Bulletin of the Global Volcanism Network, vol. 34, no. 3, March 2009 (on the Internet at http://www.volcano.si.edu/). Edited by scientists at the Smithsonian, this bulletin includes reports provided by a worldwide network of correspondents. The reports contain the names and contact information for all sources. Please note that these reports are preliminary and subject to change as events are studied in more detail. The Global Volcanism Program welcomes further reports of current volcanism, seismic unrest, monitoring data, and field observations. 相似文献
208.
209.
Sally E. Lowick Frank Preusser Roberta Pini Cesare Ravazzi 《Quaternary Geochronology》2010,5(5):583-590
Palynostratigraphical records have been used to understand the response of vegetation to climate change, and benefit from independent dating to ensure a robust correlation with global climate and sea-level change. In order to constrain the pollen chronology of a long sedimentary core taken at Azzano Decimo in the Friulian foreland of northeastern Italy, optically stimulated luminescence (OSL) has been applied to fine grain quartz. The samples meet all the standard performance criteria set to test the reliability of the single-aliquot regenerative-dose (SAR) protocol, and still show increasing dose response at 500 Gy. OSL ages are in good agreement with radiocarbon dating and the pollen interpretation down to 70 ka, and with De values of ~140 Gy, but below this point, they display an increasing age underestimation towards the Eemian and beyond. The comparison of De values measured using both a SAR and single-aliquot regeneration and added-dose (SARA) protocol, confirmed that both were successfully correcting for sensitivity changes in the quartz during measurement of the burial dose, and this was not the reason for the age underestimation. The quartz OSL dose response curve for all samples is best described by a saturating exponential plus linear (SEPL) function. Although all underestimated ages are derived from De values that fall on the high dose linear region of this curve, it is unclear if this is the cause of the underestimation. 相似文献
210.
We explored the use of hydrogen peroxide (H2O2) of different strengths (1, 3, 6, and 9%) in the preparation of lake-sediment samples for macroscopic charcoal determination.
In previous work we found that soaking sediment samples in 3% H2O2 for 24 h disaggregates samples and removes or bleaches some non-charred organic material, making it easier to distinguish
macroscopic charcoal particles from dark, non-charred organic matter. To determine whether this procedure alters charcoal
particle abundances and size distributions, we tested the procedure on wood and grass samples containing a known number of
laboratory-produced charcoal particles from different size classes (250–500, 500–1,000, and 1,000–2,000 μm). For both sample
types, we found that post-treatment numbers were not statistically different from pre-treatment numbers. However, application
of hydrogen peroxide solutions of 3, 6, and 9% to fossil charcoal assemblages in a sediment core from northwestern Costa Rica
reduced charcoal concentrations markedly, by bleaching or removing particles that were not fully charred. We also tested the
replicability of charcoal counts by conducting enumerations on multiple samples from the same stratigraphic depths in a core.
Horizontally adjacent samples from the same core may vary in charcoal concentration. This finding has implications for establishing
sample volume in macroscopic charcoal analysis. 相似文献