High-resolution spectrometer for atmospheric studies     

Piero Di Carlo  Massimiliano Barone  Alfonso D’Altorio  Cesare Dari-Salisburgo  Ermanno Pietropaolo 《Journal of Atmospheric and Solar》2009,71(12):1383-1388

A high-resolution spectrometer (0.0014 nm at 313 nm) has been developed at the University of L’Aquila (Italy) for atmospheric spectroscopic studies. The layout, optics and software for the instrument control are described. Measurements of the mercury low-pressure lamp lines from 200 to 600 nm show the high performances of the spectrometer. Laboratory measurements of OH and NO₂ spectrums demonstrate that the system could be used for cross-section measurements and to detect these species in the atmosphere. The first atmospheric application of the system was the observation of direct solar and sky spectrums that shows a filling-in of the sky lines due to rotational Raman scattering. The measurements have been done with clear and cloudy sky and in both there was a strong dependence of the filling-in from the solar zenith angle whereas no dependence from the wavelengths was evident at low solar zenith angles (less than 85°).  相似文献   

Autoscala: an aid for different ionosondes   总被引：1，自引：1，他引：0  

Michael Pezzopane  Carlo Scotto  Łukasz Tomasik  Igor Krasheninnikov 《Acta Geophysica》2010,58(3):513-526

Autoscala is a software to automatically scale ionospheric characteristics from an ionogram. Initially it was only applied to the ionograms recorded by the AIS-INGV ionosondes installed at Rome and Gibilmanna (Italy), and Tucumán (Argentina), that are not able to record the polarization of the received echo. Recently, Autoscala was also applied to the ionograms recorded by the AIS-Parus ionosonde installed at Moscow (Russia), that is not able to tag the received echo in terms of polarization, and by the VISRC2 ionosonde installed at Warsaw (Poland) that is instead able to perform the polarization tagging of the ordinary and extraordinary echoes. This work shows different examples of processing performed on ionograms recorded by all these three different types of ionosondes.  相似文献   

High-pressure/low-temperature metamorphism and the dynamics of an accretionary wedge   总被引：1，自引：0，他引：1  

Carlo Giunchi  & Yanick Ricard 《Geophysical Journal International》1999,136(3):620-628

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Stratigraphic constraints for explosive activity in the past 100 ka at Etna Volcano, Italy     

Mauro Coltelli  Paola Del Carlo  Luigina Vezzoli 《International Journal of Earth Sciences》2000,89(3):665-677

The pyroclastic deposits of Etna have been correlated over the whole volcanic edifice for the first time, allowing the construction of a continuous record of tephra-producing events, which extends from approximately 100 ka to the Present. In this interval, five main periods of explosive activity have been identified: (a) ~100-ka strombolian to subplinian activity; (b) 80- to 100-ka plinian benmoreitic activity; (c) 16- to 80-ka strombolian to subplinian from basaltic to mugearitic activity; (d) 15.5- to 15-ka plinian benmoreitic activity accompanying the caldera-forming eruptions of the Ellittico Volcano; and (e) the most recent 13-ka basaltic explosive activity of strombolian and subplinian type of the present edifice that also includes the 122-B.C. plinian eruption. This study results in a semi-quantitative and in some cases quantitative definition of the intensity and chronology of the explosive activity at Etna. Moreover, this work gives a new significance to the volcanic hazards of Etna, a volcano generally considered to be the site of gentle effusive eruptions.  相似文献   

Microalgal Communities of the Sea Ice, Ice-Covered and Ice-Free Waters of Wood Bay (Ross Sea, Antarctica) During the Austral Summer 1993 – 94     

Isabella Moro  Roberta Paccagnella  Carlo Barbante  Carlo Andreoli 《Marine Ecology》2000,21(3-4):233-245

Abstract. During the austral summer 1993 – 94, microalgal density and biomass were investigated in the sea ice, in the underlying water column, in the melt water and during the formation of the sea ice. Of the 96 taxa identified, 59 were diatoms and 32 were dinoflagellates. Among the remaining five species, Pseudopleurochloris antarctica  was very abundant both in the sea ice and in the ice-free waters. Cell densities and biomass of microalgae were higher in the bottom of the sea ice and during the formation of the ice than in the seawater, and diatoms were the dominant group at higher microalgal biomass. Among these, Entomoneis kufferathii , Chaetoceros dichaeta and Fragilariopsis species were the most common taxa.  相似文献   

Impact of a harbour construction on the benthic community of two shallow marine caves     

Ettore Nepote  Carlo Nike Bianchi  Carla Morri  Marco Ferrari  Monica Montefalcone 《Marine pollution bulletin》2017,114(1):35-45

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Observational information on a temperate reef community helps understanding the marine climate and ecosystem shift of the 1980–90s     

Giulia Gatti  Carlo Nike Bianchi  Monica Montefalcone  Sara Venturini  Giovanni Diviacco  Carla Morri 《Marine pollution bulletin》2017,114(1):528-538

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Shake table testing on restoring capability of double concave friction pendulum seismic isolation systems          下载免费PDF全文

Felice Carlo Ponzo  Antonio Di Cesare  Gianmarco Leccese  Domenico Nigro 《地震工程与结构动力学》2017,46(14):2337-2353

After an earthquake, non‐negligible residual displacements may affect the serviceability of a base isolated structure, if the isolation system does not possess a good restoring capability. The permanent offset does not affect the performance unless the design is problematic for utilities, also considering possible concerns related to the maintenance of the devices. Starting from experimental and analytical results of previous studies, the restoring capability of Double Concave Friction Pendulum bearings is investigated in this paper. A simplified design suggestion for the estimation of maximum expected residual displacements for currently used friction pendulum systems is then validated. The study is based on controlled‐displacement and seismic input experiments, both performed under unidirectional motion. Several shaking table tests have been carried out on a three‐dimensional isolated specimen structure. The same sequence of seismic inputs was applied considering three different conditions of sliding surfaces corresponding to low, medium and high friction. The accumulation of residual displacements is also investigated by means of nonlinear dynamic analysis. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

The influence of coastal dynamics on the upper limit of the Posidonia oceanica meadow     

Matteo Vacchi  Monica Montefalcone  Carlo Nike Bianchi  Carla Morri  Marco Ferrari 《Marine Ecology》2010,31(4):546-554

The recognized ecological importance of Posidonia oceanica, the most important seagrass of the Mediterranean Sea, makes it crucial to assess the state of health of its meadows, discriminating natural from anthropogenic impacts. In this paper, the hydrodynamic conditions at the upper limit of P. oceanica meadows along the Ligurian coast (NW Mediterranean Sea) were investigated. A relationship between the distance of the upper limit of the meadow from the shoreline and the morphodynamic domain of the beach (i.e. distinctive types of beach produced by the topography, wave climate and sediment composition) was found. A zonation of the state of the shallow portions of the meadows down the submerged beach profile was identified. Zone a, from the shoreline to the breaking limit, is naturally critical for the development of the meadow. Zone b, from the breaking limit to the closure depth, is subjected to natural and human impacts. Zone c, below the closure depth, is little influenced by coastal dynamics. This study quantifies for the first time how much the status of the shallow portions of P. oceanica meadows is dependent on coastal dynamics, which is important for their proper management.  相似文献   

Trace element concentrations in Coastal Hawaiian waters     

P. Bienfang  E.H. De Carlo  S. Christopher  S. DeFelice  P. Moeller 《Marine Chemistry》2009,113(3-4):164-171

The objective of this work is to characterize the concentrations of selected trace elements (V, Mn, Ni, Fe, Co, Cu, Zn, Se, As, Mo, Cd, Pb, U) in diverse nearshore (50 m), coastal (1.5 km) and seawater well environments within the Hawaiian Archipelago using robust analytical methods that are appropriate for metals analyses in seawater. The sampling sites include locations having varying type, quality and quantity of freshwater input. In most coastal and nearshore cases, the trace element concentrations approximate values characteristic of offshore waters. Concentrations of trace elements in coastal waters that were enriched through either urban or agricultural inputs declined sharply within a short distance from shore; this is taken to indicate the predominant importance of physical mixing/advective processes along with particle scavenging in these dynamic areas. Trace element levels in seawater wells did not evidence any concentration trends consistent with island age suggesting little or no impact of island weathering on metal concentrations; concentration differences among wells appeared to be more dependent on well depth, redox conditions, and/or salinity. Sampling also targeted nearshore locales where ciguatera fish poisoning is prominent because of suggested linkages between trace element concentrations and aberrant dinoflagellate growth. Nearshore stations where ciguatera is prevalent failed to show clearly different trace element levels except for two prominent locales which showed elevated Mn and Fe concentrations.  相似文献