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101.
Deborah G. Martin 《Urban geography》2013,34(4):523-540
Abstract Conflicts over siting of group homes for people transitioning out of homelessness or struggling with addiction illustrate the multiscalar dynamics at play between locally-based activism and supra-local laws. In Massachusetts, the state-scale legal environment limits the effectiveness of opposition to group housing; nonetheless, such opposition occurs at the municipal level. Drawing on media accounts, official documents, and interviews with stakeholders in conflicts over group home siting in Worcester, Massachusetts, I investigate the dynamics between neighborhood place claims, the responses of the local state, and the state-wide laws governing group home siting. Examining the legal frameworks relevant to social movement grievances demonstrate that law structures the political opportunities available for protest and local government response. 相似文献
102.
Kenneth W. Able Deborah N. Vivian Gina Petruzzelli Stacy M. Hagan 《Estuaries and Coasts》2012,35(3):743-753
We examined connectivity among marsh subhabitats to determine the structural limits and important components of a polyhaline
salt marsh by studying the patterns of abundance, residency, and movement of a numerically and ecologically dominant nektonic
fish (mummichog, Fundulus heteroclitus). We captured, tagged (n = 14,040 individuals, 30–110 mm), and recaptured from Feb 2001 to Jul 2002, although most recaptures (75–95% by tagging location)
occurred within 150 days. Seasonal residency and movements were common among most subhabitats based on catch per unit effort
and recapture per unit effort. Thus, these (marsh pools, intertidal and subtidal creeks, and marsh surface) should be considered
natural subhabitats within New England type salt marshes. Further, all these subhabitat types should be included in studies
of salt marsh nekton and marsh restoration and creation activities. 相似文献
103.
Patrizia Fiannacca Deborah Lo Pò Gaetano Ortolano Rosolino Cirrincione Antonino Pezzino 《Mineralogy and Petrology》2012,106(3-4):151-171
An ilmenite-garnet-bearing schist from the medium-grade metapelite complex of the Mandanici Unit in the Peloritani Mountains has been investigated to constrain the P-T conditions attained in this sector of the southern European Hercynian chain. Microprobe investigations assisted by statistical handling of X-ray maps via principal component analysis allowed us to better elucidate the porphyroblast-matrix relationships, the geometry of the elemental distribution in garnet porphyroblasts and the average volume percentage of the reactant garnet during retrograde metamorphic evolution. Selected microprobe data were then used to constrain, by means of P-T pseudosections, the main P-T stages of the metamorphic evolution, using the XRF bulk-rock chemistry as the equilibrium chemical composition for the prograde and peak stages and an effective bulk-rock composition for the retrograde one. Peak metamorphic P-T estimates (~530?°C; 0.9?GPa) are consistent with a Hercynian crustal thickening stage at middle-lower crustal conditions, while subsequent evolution, constrained at 420–460?°C; 0.30–0.60?GPa, depicts a retrograde clockwise P-T trajectory linked to exhumation under likely extensional shearing conditions. The results obtained in this paper lead to envisage a new scenario for the crustal evolution of the Peloritani Mountains and stimulate a revision of previous interpretations in the light of the new investigation techniques. 相似文献
104.
Climate Change Impact on Hydrological Extremes: Preliminary Results from the Polish-Norwegian Project 总被引:2,自引:1,他引:1
Renata J. Romanowicz Ewa Bogdanowicz Sisay E. Debele Joanna Doroszkiewicz Hege Hisdal Deborah Lawrence Hadush K. Meresa Jaroslaw J. Napiórkowski Marzena Osuch Witold G. Strupczewski Donna Wilson Wai Kwok Wong 《Acta Geophysica》2016,64(2):477-509
This paper presents the background, objectives, and preliminary outcomes from the first year of activities of the Polish–Norwegian project CHIHE (Climate Change Impact on Hydrological Extremes). The project aims to estimate the influence of climate changes on extreme river flows (low and high) and to evaluate the impact on the frequency of occurrence of hydrological extremes. Eight “twinned” catchments in Poland and Norway serve as case studies. We present the procedures of the catchment selection applied in Norway and Poland and a database consisting of near-natural ten Polish and eight Norwegian catchments constructed for the purpose of climate impact assessment. Climate projections for selected catchments are described and compared with observations of temperature and precipitation available for the reference period. Future changes based on those projections are analysed and assessed for two periods, the near future (2021–2050) and the far-future (2071–2100). The results indicate increases in precipitation and temperature in the periods and regions studied both in Poland and Norway. 相似文献
105.
Annual direct counts of seal pups can indicate long‐term trends in population size, but mark‐recapture estimates are needed to deduce absolute numbers. A calibration between results from these two methods would facilitate the use of direct counts to estimate absolute numbers, an outcome that is relatively quick, cheap and minimises disturbance of animals. Mark‐recapture estimates for the numbers of New Zealand fur seal (Arctocephalus forsteri) pups in 2003 at 10 colonies at Otago, southeastern New Zealand, were compared with independent single counts at the same colonies. A single ratio to estimate absolute numbers (y) from direct counts x was not statistically significant. Instead, two ratios were deduced, based on differences in habitat among colonies: y = 1.51x for colonies with hiding places for pups and y = 0.96x for colonies without hiding places. Application of these calibrations and their 95% prediction intervals produce estimates and ranges for the absolute numbers of pups from single annual counts. 相似文献
106.
Variational data assimilation for parameter estimation: application to a simple morphodynamic model 总被引:2,自引:1,他引:1
Polly J. Smith Sarah L. Dance Michael J. Baines Nancy K. Nichols Tania R. Scott 《Ocean Dynamics》2009,59(5):697-708
Data assimilation is a sophisticated mathematical technique for combining observational data with model predictions to produce
state and parameter estimates that most accurately approximate the current and future states of the true system. The technique
is commonly used in atmospheric and oceanic modelling, combining empirical observations with model predictions to produce
more accurate and well-calibrated forecasts. Here, we consider a novel application within a coastal environment and describe
how the method can also be used to deliver improved estimates of uncertain morphodynamic model parameters. This is achieved
using a technique known as state augmentation. Earlier applications of state augmentation have typically employed the 4D-Var,
Kalman filter or ensemble Kalman filter assimilation schemes. Our new method is based on a computationally inexpensive 3D-Var
scheme, where the specification of the error covariance matrices is crucial for success. A simple 1D model of bed-form propagation
is used to demonstrate the method. The scheme is capable of recovering near-perfect parameter values and, therefore, improves
the capability of our model to predict future bathymetry. Such positive results suggest the potential for application to more
complex morphodynamic models. 相似文献
107.
Deborah K. Fagan Steven R. Taylor Frederick R. Schult Dale N. Anderson 《Pure and Applied Geophysics》2009,166(4):521-545
We have developed and tested an algorithm, Bayesian Single Event Location (BSEL), for estimating the location of a seismic
event. The main driver for our research is the inadequate representation of ancillary information in the hypocenter estimation
procedure. The added benefit is that we have also addressed instability issues often encountered with historical NLR solvers
(e.g., non-convergence or seismically infeasible results). BSEL differs from established nonlinear regression techniques by
using a Bayesian prior probability density function (prior PDF) to incorporate ancillary physical basis constraints about
event location. P-wave arrival times from seismic events are used in the development. Depth, a focus of this paper, may be modeled with a prior
PDF (potentially skewed) that captures physical basis bounds from surface wave observations. This PDF is constructed from
a Rayleigh wave depth excitation eigenfunction that is based on the observed minimum period from a spectrogram analysis and
estimated near-source elastic parameters. For example, if the surface wave is an Rg phase, it potentially provides a strong constraint for depth, which has important implications for remote monitoring of nuclear
explosions. The proposed Bayesian algorithm is illustrated with events that demonstrate its congruity with established hypocenter
estimation methods and its application potential. The BSEL method is applied to three events: 1) A shallow Mw 4 earthquake
that occurred near Bardwell, KY on June 6, 2003, 2) the Mw 5.6 earthquake of July 26, 2005 that occurred near Dillon, MT,
and 3) a deep Mw 5.7 earthquake that occurred off the coast of Japan on April 22, 1980. A strong Rg was observed from the Bardwell, KY earthquake that places very strong constraints on depth and origin time. No Rg was observed for the Dillon, MT earthquake, but we used the minimum observed period of a Rayleigh wave (7 seconds) to reduce
the depth and origin time uncertainty. Because the Japan event was deep, there is no observed surface wave energy. We utilize
the prior generated from the Dillon, MT event to show that even in the case when a prior is inappropriately applied, high
quality data will overcome its influence and result in a reasonable hypocenter estimate. 相似文献
108.
Diffuse CO2 efflux near the Ukinrek Maars, two small volcanic craters that formed in 1977 in a remote part of the Alaska Peninsula, was investigated using accumulation chamber measurements. High CO2 efflux, in many places exceeding 1000 g m−2 d−1, was found in conspicuous zones of plant damage or kill that cover 30,000–50,000 m2 in area. Total diffuse CO2 emission was estimated at 21–44 t d−1. Gas vents 3-km away at The Gas Rocks produce 0.5 t d−1 of CO2 that probably derives from the Ukinrek Maars basalt based on similar δ13C values (∼−6‰), 3He/4He ratios (5.9–7.2 RA), and CO2/3He ratios (1–2 × 109) in the two areas. A lower 3He/4He ratio (2.7 RA) and much higher CO2/3He ratio (9 × 1010) in gas from the nearest arc-front volcanic center (Mount Peulik/Ugashik) provide a useful comparison. The large diffuse CO2 emission at Ukinrek has important implications for magmatic degassing, subsurface gas transport, and local toxicity hazards. Gas–water–rock interactions play a major role in the location, magnitude and chemistry of the emissions. 相似文献
109.
by Denis Cohen Mark Person Peng Wang Carl W. Gable Deborah Hutchinson ee Marksamer Brandon Dugan Henk Kooi Koos Groen Daniel Lizarralde Robert L. Evans Frederick D. Day-Lewis John W. Lane Jr. 《Ground water》2010,48(1):143-158
While the existence of relatively fresh groundwater sequestered within permeable, porous sediments beneath the Atlantic continental shelf of North and South America has been known for some time, these waters have never been assessed as a potential resource. This fresh water was likely emplaced during Pleistocene sea-level low stands when the shelf was exposed to meteoric recharge and by elevated recharge in areas overrun by the Laurentide ice sheet at high latitudes. To test this hypothesis, we present results from a high-resolution paleohydrologic model of groundwater flow, heat and solute transport, ice sheet loading, and sea level fluctuations for the continental shelf from New Jersey to Maine over the last 2 million years. Our analysis suggests that the presence of fresh to brackish water within shallow Miocene sands more than 100 km offshore of New Jersey was facilitated by discharge of submarine springs along Baltimore and Hudson Canyons where these shallow aquifers crop out. Recharge rates four times modern levels were computed for portions of New England's continental shelf that were overrun by the Laurentide ice sheet during the last glacial maximum. We estimate the volume of emplaced Pleistocene continental shelf fresh water (less than 1 ppt) to be 1300 km3 in New England. We also present estimates of continental shelf fresh water resources for the U.S. Atlantic eastern seaboard (104 km3 ) and passive margins globally (3 × 105 km3 ). The simulation results support the hypothesis that offshore fresh water is a potentially valuable, albeit nonrenewable resource for coastal megacities faced with growing water shortages. 相似文献
110.
Jonny Rutqvist Deborah Barr Jens T. Birkholzer Kiyoshi Fujisaki Olaf Kolditz Quan-Sheng Liu Tomoo Fujita Wenqing Wang Cheng-Yuan Zhang 《Environmental Geology》2009,57(6):1347-1360
This paper presents an international, multiple-code, simulation study of coupled thermal, hydrological, and mechanical (THM)
processes and their effect on permeability and fluid flow in fractured rock around heated underground nuclear waste emplacement
drifts. Simulations were conducted considering two types of repository settings (1) open emplacement drifts in relatively
shallow unsaturated volcanic rock, and (2) backfilled emplacement drifts in deeper saturated crystalline rock. The results
showed that for the two assumed repository settings, the dominant mechanism of changes in rock permeability was thermal–mechanically
induced closure (reduced aperture) of vertical fractures, caused by thermal stress resulting from repository-wide heating
of the rock mass. The magnitude of thermal–mechanically induced changes in permeability was more substantial in the case of
an emplacement drift located in a relatively shallow, low-stress environment where the rock is more compliant, allowing more
substantial fracture closure during thermal stressing. However, in both of the assumed repository settings in this study,
the thermal–mechanically induced changes in permeability caused relatively small changes in the flow field, with most changes
occurring in the vicinity of the emplacement drifts. 相似文献