Chemical composition of wet and dry atmospheric depositions in an urban environment: local,regional and long-range influences     

Luciano Morselli  Elena Bernardi  Ivano Vassura  Fabrizio Passarini  Enrico Tesini 《Journal of Atmospheric Chemistry》2008,59(3):151-170

The results of a 8 year survey of wet and dry depositions collected in Bologna (Northern Italy) are presented and discussed: monthly fluxes of the main ions (hydrogen, sodium, potassium, calcium, magnesium, ammoniacal and nitrate nitrogen, sulphate and chloride) have been registered and statistically discussed. The trend of hydrogen ion, whose largest correlation in the global deposition was found with sulphate, is clearly downwards, with peaks mainly in winter months. By means of a data factor analysis, three main sources to explain the variability of the deposition chemistry were recognized: an anthropogenic contribution (particularly represented by NO₃ ⁻, SO₄ ²⁻, H⁺), the sea spray (Na⁺, Cl⁻ and, to a lesser extent, K⁺ and Mg²⁺) and a terrigenous fraction, particularly characterized by higher Ca²⁺ concentration; however, some concentration peaks of this ion have been found in association with some episodes of Saharan dust transportation.  相似文献   

Chandra unveils a binary active galactic nucleus in Mrk 463     

Stefano Bianchi  Marco Chiaberge  Enrico Piconcelli  Matteo Guainazzi  Giorgio Matt 《Monthly notices of the Royal Astronomical Society》2008,386(1):105-110

We analyse Chandra , XMM–Newton and Hubble Space Telescope ( HST ) data of the double-nucleus Ultraluminous Infrared Galaxy (ULIRG), Mrk 463. The Chandra detection of two luminous  ( L _2–10 keV= 1.5 × 10⁴³  and  3.8 × 10⁴² erg cm⁻² s⁻¹)  , unresolved nuclei in Mrk 463 indicates that this galaxy hosts a binary active galactic nucleus (AGN), with a projected separation of ≃3.8 kpc (  3.83 ± 0.01  arcsec). While the East nucleus was already known to be a type 2 Seyfert (and this is further confirmed by our Chandra detection of a neutral iron line), this is the first unambiguous evidence in favour of the AGN nature of the West nucleus. Mrk 463 is therefore the clearest case so far for a binary AGN, after NGC 6240.  相似文献   

A structural study of cyanotrichite from Dachang by conventional and automated electron diffraction     

Gennaro Ventruti  Enrico Mugnaioli  Giancarlo Capitani  Fernando Scordari  Daniela Pinto  Andrea Lausi 《Physics and Chemistry of Minerals》2015,42(8):651-661

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Interplay between stress permutations and overpressure to cause strike‐slip faulting during tectonic inversion          下载免费PDF全文

David C. P. Peacock  Enrico Tavarnelli  Mark W. Anderson 《地学学报》2017,29(1):61-70

Field data from an orogenic foreland and an orogenic belt (the Mesozoic rocks of southern England and the Umbria‐Marche Apennines of Italy respectively) indicate the following. Firstly, stress evolution during the tectonic cycle, between maximum compressive stress (σ₁) being vertical during extension and least compressive stress (σ₃) being vertical during contraction, can involve phases when the intermediate compressive stress (σ₂) is vertical, promoting strike‐slip deformation. Secondly, variations in the relative magnitudes of the stress axes are caused by variations in overburden and tectonic forces. Thirdly, overpressure can develop because of compaction during burial, and, as overburden is reduced during uplift and erosion, the vertical stress (σ_V) reduces but fluid pressure (P_f) remains approximately constant. Brittle deformation, including transient strike‐slip faults, reverse‐reactivated normal faults and normal‐reactivated thrusts, is preferentially developed in overpressured areas because high P_f promotes faulting.  相似文献   

Intrinsic vulnerability assessment of Saturnia thermal aquifer by means of three parametric methods: SINTACS,GODS and COP   总被引：2，自引：1，他引：1  

Enrico Guastaldi  Luca Graziano  Giovanni Liali  Fabio Nunzio Antonio Brogna  Alessio Barbagli 《Environmental Earth Sciences》2014,72(8):2861-2878

Three different parametric methods for the evaluation of intrinsic vulnerability to pollution have been applied in a hydrothermal carbonate aquifer located in central-northern Italy and the results obtained were compared with each other. The study area, large, approximately 152 km², lies in an area of the northern Apennines. The investigated aquifer feeds the hot thermal springs of Saturnia. The vulnerability assessment methods used are: SINTACS, GODS and COP. The vulnerability maps obtained were first individually examined, and then they were compared with each other by means of spatial analysis. These maps show similar results for the estimation of the vulnerability just in some areas. SINTACS yields areas potentially vulnerable to pollution along the Albegna River and its major tributaries in the northern part of the study area. The GODS index map reflects the great importance that this method gives to the lithological characteristics of the unsaturated zone in the subdivision of areas with different vulnerability. GODS and COP methods agree in classifying low vulnerability in the most part of central-southern study area, where the aquifer is confined by the Pliocene clay deposits. Based on the conceptual model of groundwater flow developed for the aquifer under investigation, COP seems the most appropriate method among those applied in this work, in particular with regard to the assessment of the vulnerability of the recharge area of thermal groundwater. Located in the northern part of the study area, where karst carbonate formations of the Tuscan Nappe outcrop, this recharge area is classified by the COP method as highly vulnerable to pollution.  相似文献   

Science & Technology: A Synergic Cooperation. The Italian Experience in the Cassini Mission     

E. Flamini  R. Somma 《Earth, Moon, and Planets》2005,96(3-4):101-108

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On the reliability of the equivalent frame models: the case study of the permanently monitored Pizzoli’s town hall     

Degli Abbati  Stefania  Morandi  Paolo  Cattari  Serena  Spacone  Enrico 《Bulletin of Earthquake Engineering》2022,20(4):2187-2217

Bulletin of Earthquake Engineering - This paper presents the comparison of the results of modal and nonlinear analyses carried out on a 2-story masonry building with rigid diaphragms, inspired by...  相似文献   

Time-dependent reliability analysis of unsaturated slopes under rapid drawdown with intelligent surrogate models     

Guardiani  Carlotta  Soranzo  Enrico  Wu  Wei 《Acta Geotechnica》2022,17(4):1071-1096

Acta Geotechnica - Slope stability in reservoirs depends on time-dependent triggering factors such as fluctuations of the groundwater level and precipitation. This paper assesses the stability of...  相似文献   

An Advanced Systematic Literature Review on Spatiotemporal Analyses of Twitter Data   总被引：4，自引：1，他引：3       下载免费PDF全文

Enrico Steiger  João Porto de Albuquerque  Alexander Zipf 《Transactions in GIS》2015,19(6):809-834

The objective of this article is to conduct a systematic literature review that provides an overview of the current state of research concerning methods and application for spatiotemporal analyses of the social network Twitter. Reviewed papers and their application domains have shown that the study of geographical processes by using spatiotemporal information from location‐based social networks represent a promising and still underexplored field for GIScience researchers.  相似文献   

High-mass X-ray binaries in the Milky Way     

Roland Walter  Alexander A. Lutovinov  Enrico Bozzo  Sergey S. Tsygankov 《Astronomy and Astrophysics Review》2015,23(1):1-99

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