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111.
Marini M Betti M Grati F Marconi V Mastrogiacomo AR Polidori P Sanxhaku M 《Marine pollution bulletin》2012,64(3):472-478
This study aimed to analyze the impact at sea of a pesticide factory located 7 km north of Durres (Albania) by investigating a lowland area under the sea situated 0.7 km from the shoreline. The main product of this factory was lindane. Production ceased in 1991 during the Albanian civil war, and a large amount of industrial waste was dispersed over the ground surrounding the factory, resulting in a high level of lindane pollution. A water-scoop channels the ground water accumulated around the disused factory directly into the sea. The concentrations of lindane in sediments collected along the coasts of the region ranged from 0.60 to 22.55 ng g(-1). The average concentration in the muscles of fish did not exceed the limits specified by European Commission legislation, whereas the concentration in the liver did exceed these limits; consequently, liver is not recommended for consumption. 相似文献
112.
We use different interferometry approaches to process the seismic signals generated by a drill‐bit source in one well and recorded by seismic receivers located both in a second borehole and at the surface near the source well. We compare the standard interferometry results, obtained by using the raw drill‐bit data without a pilot signal, with the new interferometry results obtained by using the drill‐bit seismograms correlated with a reference pilot signal. The analysis of the stationary phase shows that the final results have different S/N levels and are affected by the coherent noise in the form of rig arrivals. The interferometry methods are compared by using different deconvolution approaches. The analysis shows that the results agree with the conventional drill‐bit seismograms and that using the reference pilot signal improves the quality of the drill‐bit wavefields redatumed by the interferometry method. 相似文献
113.
114.
Piero Galeotti 《Astrophysics and Space Science》1970,7(1):87-92
New spectroscopic elements of R Canis Majoris are given in this paper, computed from 17 plates secured at the Astronomical Observatory of Merate. A new orbit has also been computed with the program by Bertiau, from 81 observations covering a period of about 40 years.Two models of this binary system are proposed, based on two different assumptions and on a newly determined mass function. It is confirmed that the main peculiarity of this binary with regard to the mass-luminosity relation is real; there is also an evidence of mass loss from the Lagrangian pointL
2 as suggested by Kitamura.A suspected variation of the velocityV
0 of the center of mass seems to indicate the presence of a third body. The evidnece is, however, not yet conclusive. 相似文献
115.
Summary Results are presented and discussed from a testing program to study the flexural strength of a rock-like material. In order
to investigate the size effects, experiments were performed using specimens of a medium grained size granite. For geometrically
similar beams of different sizes, this paper presents and discusses experimental evidence from interferometric measurements
(ESPI) and locations of acoustic emissions (AE) of the damage zone development, at the peak load, in terms of shape and size.
The bending strengths are compared with the direct tensile strength obtained with double-edge-notched specimens. The experimental
strengths are interpreted with a stress analysis in the critical cross-section that takes into account the influence of the
localized region of microcracks arising when peak load is approached. 相似文献
116.
Occurrence of Irgarol 1051 and its major metabolite in Maryland waters of Chesapeake Bay 总被引:1,自引:0,他引:1
Irgarol and its major metabolite (GS26575) were measured in Maryland waters of Chesapeake Bay: (1) in and near 10 marinas, a mainstem Bay site and two Severn River locations during a general survey in July and December of 2002; (2) at various sites in the Port Annapolis Marina and the Severn River area during March of 2002 before the boating season began; and (3) during July (peak boating season) in the same Port Annapolis Marina and Severn River sites area during both an ebb and flood tide. Irgarol concentrations ranged from 1.82 ng/l at the mid-Bay site to 585 ng/l in Port Annapolis marina during the July and December general survey. An Irgarol 90th centile of 239 ng/l was reported for the 10 marina sites, two Severn River sites and one mainstem site sampled during the general survey conducted in July and December. Temporal analysis of all pooled data showed that 90th centiles were over seven times higher in July when compared to December. A comparison of Irgarol concentrations at 12 sites in the Port Annapolis marina and Severn River area during both an ebb and flood tide in July showed no consistent trend with tidal cycle by site although significant reductions in concentrations were reported with distance from the three Port Annapolis marina sites. Ecological risk from Irgarol exposure was judged to be low for most Chesapeake Bay sites sampled. Possible exceptions were Port Annapolis marina, Severn River sites in close proximity to this marina and Chesapeake Harbor marina where Irgarol concentrations exceeded a conservative effects threshold during the peak boating season in July. Ecological risk from GS26575 exposure was low for all sites. 相似文献
117.
Piero Comin-Chiaramonti Celso B. Gomes Angelo De Min Excelso Ruberti Vicente A. V. Girardi Francesca Slejko Renato D. Neder Francisco E. C. Pinho 《Central European Journal of Geosciences》2014,6(4):565-587
The Planalto da Serra igneous rocks form plugs, necks and dykes of carbonate-rich ultramafic lamprophyres (aillikites and glimmerites with kamafugitic affinity) and carbonatites (alvikites and beforsites). Phlogopite and/or tetraphlogopite, diopside and melanitic garnet are restricted to aillikitic rock-types, whereas pyroclore occurs only in carbonatites. Aillikites and carbonatites are altered to hydrotermalites, having chlorite and serpentine as dominant minerals. Planalto da Serra igneous rock association has kamafugitic affinity (i.e. effusive, ultrapotassic. High LREE/HREE fractionation, incompatible elements data and Sr-Nd isotopes, suggest that the K-ultramafic alkaline and carbonatite rocks originated from a variably metasomatized mantle source enriched in radiogenic Sr. Crustal contamination is negligible or absent. Age values of 600 Ma rule out the geochronological relationship between the investigated intrusions and the Mesozoic alkaline bodies from the Azimuth 125° lineament. The TDM model ages allow to conclude that Planalto da Serra magma is derived from the partial melting of a mantle source metasomatised by K-rich carbonatated melt during the Early to Late Neoproterozoic. On the basis of alkaline magmatism repetitions at 600 Ma and 90–80 Ma we question the subsistence of a stationary mantle plume for so long time. 相似文献
118.
June-Yi Lee Bin Wang I.-S. Kang J. Shukla A. Kumar J.-S. Kug J. K. E. Schemm J.-J. Luo T. Yamagata X. Fu O. Alves B. Stern T. Rosati C.-K. Park 《Climate Dynamics》2010,35(2-3):267-283
Given observed initial conditions, how well do coupled atmosphere–ocean models predict precipitation climatology with 1-month lead forecast? And how do the models’ biases in climatology in turn affect prediction of seasonal anomalies? We address these questions based on analysis of 1-month lead retrospective predictions for 21 years of 1981–2001 made by 13 state-of-the-art coupled climate models and their multi-model ensemble (MME). The evaluation of the precipitation climatology is based on a newly designed metrics that consists of the annual mean, the solstitial mode and equinoctial asymmetric mode of the annual cycle, and the rainy season characteristics. We find that the 1-month lead seasonal prediction made by the 13-model ensemble has skills that are much higher than those in individual model ensemble predictions and approached to those in the ERA-40 and NCEP-2 reanalysis in terms of both the precipitation climatology and seasonal anomalies. We also demonstrate that the skill for individual coupled models in predicting seasonal precipitation anomalies is positively correlated with its performances on prediction of the annual mean and annual cycle of precipitation. In addition, the seasonal prediction skill for the tropical SST anomalies, which are the major predictability source of monsoon precipitation in the current coupled models, is closely link to the models’ ability in simulating the SST mean state. Correction of the inherent bias in the mean state is critical for improving the long-lead seasonal prediction. Most individual coupled models reproduce realistically the long-term annual mean precipitation and the first annual cycle (solstitial mode), but they have difficulty in capturing the second annual (equinoctial asymmetric) mode faithfully, especially over the Indian Ocean (IO) and Western North Pacific (WNP) where the seasonal cycle in SST has significant biases. The coupled models replicate the monsoon rain domains very well except in the East Asian subtropical monsoon and the tropical WNP summer monsoon regions. The models also capture the gross features of the seasonal march of the rainy season including onset and withdraw of the Asian–Australian monsoon system over four major sub-domains, but striking deficiencies in the coupled model predictions are observed over the South China Sea and WNP region, where considerable biases exist in both the amplitude and phase of the annual cycle and the summer precipitation amount and its interannual variability are underestimated. 相似文献
119.
Piero Tempesti 《Astronomische Nachrichten》1979,300(1):51-55
On the basis of photoelectric observations performed at the Teramo Observatory, the V lightcurve of Nova Cygni 1975 from August 1975 to July 1977 is given. Since three days after maximum thereafter, the decline pursued smoothly according the law V = 2.5 + 3.9 lg t, and 680 days after maximum the star had weakened by 12.5 mag. The well-known shortperiod light variation, which at the time of the early decline showed an amplitude smaller than 0.2 mag in V light, on December 13, 1976, displayed an amplitude as high as 0.5 mag. 相似文献
120.
Acta Geotechnica - Caisson foundations, typically adopted for both onshore and offshore structures, are usually subject to combined loading acting during working conditions and exceptional events... 相似文献