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101.
Roberto Danovaro Norberto Della Croce Antonio Dell'Anno Mauro Fabiano Daniela Marrale Daniela Martorano 《Progress in Oceanography》2000,46(2-4)
Downward fluxes of labile organic matter (lipids, proteins and carbohydrates) at 200 (trap A) and 1515 m depth (trap B), measured during a 12 months sediment trap experiment, are presented, together with estimates of the bacterial and cyanobacterial biomasses associated to the particles. The biochemical composition of the settling particles was determined in order to provide qualitative and quantitative information on the flux of readily available organic carbon supplying the deep-sea benthic communities of the Cretan Sea. Total mass flux and labile carbon fluxes were characterised by a clear seasonality. Higher labile organic fluxes were reported in trap B, indicating the presence of resuspended particles coming from lateral inputs. Particulate carbohydrates were the major component of the flux of labile compounds (on annual average about 66% of the total labile organic flux) followed by lipids (20%) and proteins (13%). The biopolymeric carbon flux was very low (on annual average 0.9 and 1.2 gC m−2 y−1, at trap A and B). Labile carbon accounted for most of the OC flux (on annual average 84% and 74% in trap A and B respectively). In trap A, highest carbohydrate and protein fluxes in April and September, corresponded to high faecal pellet fluxes. The qualitative composition of the organic fluxes indicated a strong protein depletion in trap B and a decrease of the bioavailability of the settling particles as a result of a higher degree of dilution with inorganic material. Quantity and quality of the food supply to the benthos displayed different temporal patterns. Bacterial biomass in the sediment traps (on average 122 and 229 μgC m−2 d−1 in trap A and B, respectively) was significantly correlated to the flux of labile organic carbon, and particularly to the protein and carbohydrate fluxes. Cyanobacterial flux (on average, 1.1 and 0.4 μgC m−2 d−1, in trap A and B, respectively) was significantly correlated with total mass and protein fluxes only in trap A. Bacterial carbon flux, equivalent to 84.2 and 156 mgC m−2 y−1, accounted for 5–6.5% of the labile carbon flux (in trap A and B respectively) and for 22–41% protein pool of the settling particles. These results suggest that in the Cretan Sea, bacteria attached to the settling particles represent a potential food source of primary importance for deep-sea benthic communities. 相似文献
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105.
Giusj Valentina Fichera Cristina Maria Belfiore Mauro Francesco La Russa Silvestro Antonio Ruffolo Donatella Barca Riccardo Frontoni Giuliana Galli Antonino Pezzino 《Geoarchaeology》2015,30(2):79-99
Roman mortars were collected from the Villa dei Quintili in Rome, an archaeological site consisting of numerous edifices from nine construction phases dating from the 2nd century A.D. to modern times. A multianalytical approach was used on 34 mortar samples to infer the evolution of production techniques over time and to identify the source area of calcareous raw materials used in the preparation of the lime. Optical microscopy, scanning electron microscopy coupled with an energy‐dispersive system, and laser ablation inductively coupled plasma mass spectrometry were used to study the samples. The major and trace element data were compared with the compositions of two types of limestone samples (Calcare Massiccio and Calcare Maiolica) collected from the Cornicolani Mountains. The results suggest that the technological practices and the calcareous raw materials used for lime production remained unchanged over the time period considered (2nd century A.D. to 3rd century A.D.). The compositions of lime‐related particles in the mortars match those of Calcare Maiolica, which suggests its use as raw material for lime production. On the whole, the results are in agreement with data from existing literature regarding both the use by Roman builders of specific raw materials for the mortars’ production and the relative supply area. 相似文献
106.
The Averno 2 fissure eruption: a recent small-size explosive event at the Campi Flegrei Caldera (Italy) 总被引:1,自引:0,他引:1
Mauro Antonio Di Vito Ilenia Arienzo Giuseppe Braia Lucia Civetta Massimo D’Antonio Valeria Di Renzo Giovanni Orsi 《Bulletin of Volcanology》2011,73(3):295-320
The Averno 2 eruption (3,700 ± 50 a B.P.) was an explosive low-magnitude event characterized by magmatic and phreatomagmatic
explosions, generating mainly fall and surge beds, respectively. It occurred in the Western sector of the Campi Flegrei caldera
(Campanian Region, South Italy) at the intersection of two active fault systems, oriented NE and NW. The morphologically complex
crater area, largely filled by the Averno lake, resulted from vent activation and migration along the NE-trending fault system.
The eruption generated a complex sequence of pyroclastic deposits, including pumice fall deposits in the lower portion, and
prevailing surge beds in the intermediate-upper portion. The pyroclastic sequence has been studied through stratigraphical,
morphostructural and petrological investigations, and subdivided into three members named A through C. Member A was emplaced
during the first phase of the eruption mainly by magmatic explosions which generated columns reaching a maximum height of
10 km. During this phase the eruption reached its climax with a mass discharge rate of 3.2 106 kg/s. Intense fracturing and fault activation favored entry of a significant amount of water into the system, which produced
explosions driven by variably efficient water-magma interaction. These explosions generated wet to dry surge deposits that
emplaced Member B and C, respectively. Isopachs and isopleths maps, as well as areal distribution of ballistic fragments and
facies variation of surge deposits allow definition of four vents that opened along a NE oriented, 2 km long fissure. The
total volume of magma extruded during the eruption has been estimated at about 0.07 km3 (DRE). The erupted products range in composition from initial, weakly peralkaline alkali-trachyte, to last-emplaced alkali-trachyte.
Isotopic data and modeling suggest that mixing occurred during the Averno 2 eruption between a more evolved, less radiogenic
stored magma, and a less evolved, more radiogenic magma that entered the shallow reservoir to trigger the eruption. The early
phases of the eruption, during which the vent migrated from SW to the center of the present lake, were fed by the more evolved,
uppermost magma, while the following phases extruded the less evolved, lowermost magma. Integration of the geological and
petrological results suggests that the Averno 2 complex eruption was fed from a dyke-shaped shallow reservoir intruded into
the NE-SW fault system bordering to the west the La Starza resurgent block, within the caldera floor. 相似文献
107.
Overview of the Italian strong motion database ITACA 1.0 总被引:3,自引:2,他引:1
Francesca Pacor Roberto Paolucci Lucia Luzi Fabio Sabetta Andrea Spinelli Antonella Gorini Mario Nicoletti Sandro Marcucci Luisa Filippi Mauro Dolce 《Bulletin of Earthquake Engineering》2011,9(6):1723-1739
The Italian Strong Motion Database, ITACA, was developed within projects S6 and S4, funded in the framework of the agreements
between the Italian Department of Civil Protection (Dipartimento della Protezione Civile, DPC) and the Istituto Nazionale
di Geofisica e Vulcanologia (INGV), starting from 2005. The alpha version of the database was released in 2007 and subsequently
upgraded to version 1.0 after: (i) including the most recent strong motion data (from 2005 to 2007) recorded in Italy, in
addition to the 2008 Parma earthquake, M 5.4, and the M ≥ 4.0, 2009 Abruzzo seismic events; (ii) processing the raw strong
motion data using an updated procedure; (iii) increasing the number of stations with a measured shear wave velocity profile;
(iv) improving the utilities to retrieve time series and ground motion parameters; (v) implementing a tool for selecting time
series in agreement with design-response spectra; (vi) compiling detailed station reports containing miscellaneous information
such as photo, maps and site parameters; (vii) developing procedures for the automatic generation of station reports and for
the updating of the header files. After such improvements, ITACA 1.0 was published at the web site , in 2010. It presently contains 3,955 three-component waveforms, comprising the most complete catalogue of the Italian accelerometric
records in the period 1972–2007 (3,562 records) and the strongest events in the period 2008–2009. Records were mainly acquired
by DPC through its Accelerometric National Network (RAN) and, in few cases, by local networks and temporary stations or networks.
This paper introduces the published version of the Italian Strong Motion database (ITACA version 1.0) together with main improvements
and new functionalities. 相似文献
108.
Barbara Borzi Fabio Dell��Acqua Marta Faravelli Paolo Gamba Gianni Lisini Mauro Onida Diego Polli 《Bulletin of Earthquake Engineering》2011,9(2):675-690
The aim of this paper is to disseminate knowledge in the seismic science community about a possible tool which is not largely
popular, despite its potential usefulness. In this paper it will be shown how satellite remotely sensed images may represent
a powerful source of information where traditional sources of information are unable to deliver it, or at least to do so timely.
Even when traditional information flow can ensure delivery, an advantage may still be found in terms of sooner availability
and smaller amount of labour required. In the case shown here a vulnerability study was made on a vast industrial area in
the gulf of Siracusa, Sicily, Italy. A series of concurrent factors made it particularly troublesome to obtain information
on the structures found in the site (tanks, pipes, chimneys, roads, ...), required to suitably carry out the study. Satellite
images were then acquired to obtain the information needed. Processing of the images was carried out relying on in-house software
formerly developed for similar information extraction issues, and integrated with new, specifically developed elements, some
pieces of information were obtained useful for seismic risk evaluation. In particular, location, footprint, elevation of significant
structures (e.g. tanks, chimneys) could be evaluated, obtaining results in a format compatible with the most widespread GIS
(Geographic Information System) standards. Such compatibility allowed a considerable savings on labour time required to lay
a GIS of the area, which is a fundamental tool for risk and vulnerability analyses. 相似文献
109.
Mauro Coltorti Andrea Brogi Lorenzo Fabbrini Dario Firuzabadì Lapo Pieranni 《Natural Hazards》2011,59(1):191-208
The eastern side of the Mt. Amiata volcano is affected by a series of deep-seated gravitational slope deformations (DsGSDs).
The San Piero and the Podere Mezzavia DsGSDs affect the lower part of the slope. The main escarpments are located on the outer
edges of the lava flows, but the landslides mostly affect the pre-volcanic Ligurian Terrains. A deeper movement, possibly
exceeding 100 m in thickness, is evidenced by a long trench at the base of the main escarpment that indicates a sagging type
movement. This deeper movement is responsible for the activation of a series of superficial rock and mud flows that show evidence
of ongoing activity. The most likely location of the sliding surface is the tectonized contact between the Santa Fiora and
Argille a Palombini Fms within the Ligurian units, although the superficial landslides prevent our determining with certainty
if a clear-cut sliding surface already developed connecting the upper and the lower parts of the slope. These DsGSDs were
activated along the flanks of a larger movement that affects the lava flow units cropping out in the middle slope of the volcano.
A long main escarpment, secondary escarpments, trenches and borehole data suggest that the thickness could locally exceed
200 m and generate another sagging type movement. Up-slope and up-movement-facing counterscarps indicate the existence of
a listric elongated spoon-shaped compound embryonic sliding surface. This sagging, which hosts the towns of Abbadia San Salvatore
and Piancastagnaio, appears to be in a quiescent stage, according to preliminary monitoring with a global positioning system
(GPS) network. The downcutting of the river network along the softer Pliocene terrains of the Radicofani basin is enhanced
by the general uplift of the Apennines and seems to be the major factor in the activation of these DsGSDs. 相似文献
110.
Mauro F. La Russa Germana Barone Cristina M. Belfiore Paolo Mazzoleni Antonino Pezzino 《Environmental Earth Sciences》2011,62(6):1263-1272
Noto is an important Baroque urban center in south-eastern Sicily, which was completely reconstructed after the severe earthquake
of 1693. Most of its monuments and historic buildings were built in Pietra di Noto stone, a pale cream calcarenite, quarried
in outcrops located near the city. This stone, still currently used as building material, is undergoing many forms of alteration
and degradation, which cause significant damage to monuments. In this study, three commercial protective products were tested
on some Noto calcarenite samples from quarries, with the aim of assessing their protective effectiveness. In particular, petrographic
analyses by optical microscopy were carried out for textural characterization of the stone materials. Capillary water absorption,
porosimetric and colorimetric procedures, UV radiation and salt crystallization aging tests were performed to better evaluate
interactions between protective products and substrate. 相似文献