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11.
M. Picotti 《Meteorology and Atmospheric Physics》1954,7(1):466-476
Zusammenfassung Die physikalischen und chemischen Verhältnisse der Gewässer der oberen Adria wurden während einer Frühlings- und einer Sommerperiode längs des 45. Breitenkreises beobachtet. Die Gleichzeitigkeit der Messungen wurde mit Hilfe dreier funkkommandierter Schiffe erreicht. Dabei zeigten sich folgende Unterschiede der Umwelteinflüsse: Die Gewässer der östlichen und der mittleren Zone gleichen dem reinen Meerwasser aus dem Süden, während die der westlichen Zone von den Zuflüssen der Flüsse beeinflußt sind.
Mit 4 Textabbildungen. 相似文献
Summary An investigation of the physico-chemical conditions of the waters of the upper Adriatic has been carried out during a spring and a summer period along the 45th parallel. Due to the measurements being taken by three radio-commanded ships it was possible to effect them at exactly the same time. Water-conditions differ according to location: In the eastern and central zone the water corresponds to the pure sea-water coming from the south, while in the western zone the water is influenced by fluvial affluents.
Résumé Les conditions physiques et chimiques des eaux de la Haute-Adriatique ont été observées pendant une période de printemps et une période d'été, le long d'une section à la hauteur du 45ème parallèle; la simultanéité des recherches était assurée, car les mesures furent effectuées par trois navires radiocommandés. Les états du milieu des eaux sont différents: celles des zones orientale et centrale correspondent aux eaux marines pures venant du sud tandis que dans la zone occidentale elles sont influencées par des affluents fluviaux.
Riassunto Le condizioni fisico-chimiche delle acque dell'Alto Adriatico sono state osservate in un periodo primaverile ed in uno estivo lungo una sezione al 45° parallelo; la contemporaneità delle misure è stata assicurata a mezzo di misure effettuate con tre navi radiocomandate. Le condizioni ambientali delle acque sono diverse: quelle della zona orientale e centrale corrispondono alle acque marine pure provenienti dal sud, mentre nella zona occidentale le acque sono influenzate dal deflusso fluviale.
Mit 4 Textabbildungen. 相似文献
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Vincenzo Amico Giuseppe Impellizzeri Giovanna Oriente Mario Piattelli Sebastiano Sciuto Corrado Tringali 《Marine pollution bulletin》1979,10(10):282-284
Concentrations of chlorinated hydrocarbons (DDT and metabolites, PCBs, aldrin, dieldrin, HCB and BHCs) have been determined in the tissues of five species of marine animals sampled in selected areas of the central Mediterranean. 相似文献
14.
Vincenzo Amico Giovanna Oriente Mario Piattelli Corrado Tringali 《Marine pollution bulletin》1979,10(6):177-179
The levels of PCBs, DDT and BHC residues have been determined in thalli of 12 species of marine algae harvested along the east coast of Sicily. The results are discussed in comparison with those obtained earlier with animal species sampled in the same area. 相似文献
15.
Antonietta Grande Gianfranco Di Vincenzo Giacomo Prosser Alfredo Caggianelli 《地学学报》2009,21(4):293-303
The Variscan crystalline basement of the Calabria–Peloritani terrane (CPT) in southern Italy was partly reworked by ductile and brittle shear zones throughout the Alpine tectonic evolution (from thickening to exhumation). Although evidence of extensional tectonics in the CPT has already been found and roughly constrained to the Oligocene onward, no attempt has ever been made to directly date brittle fault movements. Structural (meso- and micro-scale), kinematic and petrographic analyses and 40 Ar–39 Ar laser experiments reveal that the pseudotachylyte-bearing shear zones of the Palmi area in southern Calabria formed in response to extensional shearing ∼33.5 Ma ago and overprinted compressional tectonic structures. Results provide the first direct evidence of Middle Oligocene co-seismic faulting in the area and confirm the role of extensional tectonics in promoting the Oligocene exhumation of the Calabria basement. 相似文献
16.
Vincenzo Festa Giacomo Prosser Alfredo Caggianelli Antonietta Grande Antonio Langone Daniela Mele 《Geological Journal》2016,51(4):670-681
New microstructural data on the mylonites from the well‐exposed Palmi shear zone (southern Calabria) are presented with the aim to shed light on both the kinematics and the geometry of the southwestern branch of the Alpine belt during Eocene. In the study area, located between the Sardinia–Corsica block and the Calabria–Peloritani terrane, previous large‐scale geodynamic reconstructions suggest the presence of strike–slip or transform fault zones dissecting the southwestern branch of the Alpine belt. However, there are no field data supporting the occurrence of these structures. This paper uses vorticity analysis technique based on the aspect ratio and the long axis orientation of rigid porphyroclasts in mylonitic marbles and mylonitic granitoids, to estimate the contribution of pure and simple shear of deformation during the movement of the Palmi shear zone. Porphyroclasts aspect ratio and orientation were measured on thin sections using image analysis. Estimates of the vorticity number, Wm, indicate that the Palmi shear zone recorded general shear with a contribution of pure shear of c. 65%. Then, the Palmi shear zone can be interpreted as a segment of a left‐lateral transpressive bend along the southern termination of the Eocene Alpine front. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
17.
Enrico Costa Ronaldo Bellazzini Gianpiero Tagliaferri Giorgio Matt Andrea Argan Primo Attinà Luca Baldini Stefano Basso Alessandro Brez Oberto Citterio Sergio Di Cosimo Vincenzo Cotroneo Sergio Fabiani Marco Feroci Antonella Ferri Luca Latronico Francesco Lazzarotto Massimo Minuti Ennio Morelli Fabio Muleri Lucio Nicolini Giovanni Pareschi Giuseppe Di Persio Michele Pinchera Massimiliano Razzano Luigia Reboa Alda Rubini Antonio Maria Salonico Carmelo Sgro’ Paolo Soffitta Gloria Spandre Daniele Spiga Alessio Trois 《Experimental Astronomy》2010,28(2-3):137-183
Since the birth of X-ray astronomy, spectral, spatial and timing observation improved dramatically, procuring a wealth of information on the majority of the classes of the celestial sources. Polarimetry, instead, remained basically unprobed. X-ray polarimetry promises to provide additional information procuring two new observable quantities, the degree and the angle of polarization. Polarization from celestial X-ray sources may derive from emission mechanisms themselves such as cyclotron, synchrotron and non-thermal bremsstrahlung, from scattering in aspheric accreting plasmas, such as disks, blobs and columns and from the presence of extreme magnetic field by means of vacuum polarization and birefringence. Matter in strong gravity fields and Quantum Gravity effects can be studied by X-ray polarimetry, too. POLARIX is a mission dedicated to X-ray polarimetry. It exploits the polarimetric response of a Gas Pixel Detector, combined with position sensitivity, that, at the focus of a telescope, results in a huge increase of sensitivity. The heart of the detector is an Application-Specific Integrated Circuit (ASIC) chip with 105,600 pixels each one containing a full complete electronic chain to image the track produced by the photoelectron. Three Gas Pixel Detectors are coupled with three X-ray optics which are the heritage of JET-X mission. A filter wheel hosting calibration sources unpolarized and polarized is dedicated to each detector for periodic on-ground and in-flight calibration. POLARIX will measure time resolved X-ray polarization with an angular resolution of about 20 arcsec in a field of view of 15 × 15 arcmin and with an energy resolution of 20% at 6 keV. The Minimum Detectable Polarization is 12% for a source having a flux of 1 mCrab and 105 s of observing time. The satellite will be placed in an equatorial orbit of 505 km of altitude by a Vega launcher. The telemetry down-link station will be Malindi. The pointing of POLARIX satellite will be gyroless and it will perform a double pointing during the earth occultation of one source, so maximizing the scientific return. POLARIX data are for 75% open to the community while 25% + SVP (Science Verification Phase, 1 month of operation) is dedicated to a core program activity open to the contribution of associated scientists. The planned duration of the mission is one year plus three months of commissioning and SVP, suitable to perform most of the basic science within the reach of this instrument. A nice to have idea is to use the same existing mandrels to build two additional telescopes of iridium with carbon coating plus two more detectors. The effective area in this case would be almost doubled. 相似文献
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19.
The Northern Tyrrhenian Sea is located on the collisional zone between the Alpine Corsica and the Northern Apennines and is a key area for gaining a better understanding of the complex relationships between these two systems. The knowledge of the wide offshore part of this zone, located between Corsica (France) and mainland Italy, is based primarily on the analysis of several seismic profiles tied to the outcropping geology and unpublished preliminary reports of few offshore wells. The here presented study of two offshore wells provides a revision of the sedimentology, biostratigraphy and petrography of the thick, mainly siliciclastic, Tertiary successions (about 3,600 m) composing the Elba–Pianosa Ridge (EPR), a structural/morphological high separating the Tuscan Shelf to the east from the Corsica Basin to the west. A comparison with similar deposits cropping out in the surrounding onshore areas (Northern Apennines, Corsica, Tuscan Archipelago, Piedmont Tertiary Basin) provides additional constraints for refinement of the complex geodynamic and regional setting in which the EPR evolved. 相似文献
20.
This work presents a geomorphometric approach for outlining anomalies of the topographic surface that may be related to geological structures or to geomorphological phenomena. It is based on 2D discrete wavelet transform of digital elevation models. This transform is used to extract singularities of a series of data. This is specifically applied to a digital elevation model, in order to get its detail coefficients and to have evidence about their variations and values. In particular, this approach can be helpful for the delineation and identification of landforms singularities, like landslides and geological structures. The potential and effectiveness of this approach is shown by an application to a case study about a large deep-seated landslide, located at the central-south front of the Apennine in South Italy. 相似文献