A simple and generalised <Emphasis Type="Italic">P–T–V</Emphasis> EoS for continuous phase transitions,implemented in EosFit and applied to quartz     

Ross?J.?AngelEmail authorView author&#;s OrcID profile  Matteo?Alvaro  Ronald?Miletich  Fabrizio?Nestola 《Contributions to Mineralogy and Petrology》2017,172(5):29

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Resilience and seismic risk perception at school: a geoethical experiment in Aiello Calabro,southern Italy     

Francesco De Pascale  Marcello Bernardo  Francesco Muto  Dante Di Matteo  Valeria Dattilo 《Natural Hazards》2017,86(2):569-586

The last few years have seen the debate on the geoethics of environmental and climatic protection growing to include resilience as a central idea within this new discipline, which holds many similarities with geography. Resilience analysis often looks at the capacity to re-establish conditions of equilibrium within a system which has been hit by a serious shock, e.g. a natural or man-made disaster. Geoethics works, in tandem with geological analyses and the geography of risk, to inform a population and develop integrated risk management in such a way as to strengthen a community’s resilience. The aim of this work is to study some people’s capacity to overcome what was potentially a disastrous event and, through a process of reconstruction, turn it into an occasion for growth. The experiment, carried out in the primary and middle schools in Aiello Calabro (Calabria, southern Italy), was conducted on the basis of the belief that there is a close relationship between a population’s having a realistic understanding of the risk of such an event, e.g. an earthquake, and high levels of resilience. We also tried to gain an insight into the relationship that may exist between resilience in primary and secondary school children and methods of coping which give an appropriate management of seismic risk. To be more precise, we try to discover whether there is a link between good/appropriate resilience and good/appropriate risk management.  相似文献   

Radial growth change of temperate tree species in response to altered regional climate and air quality in the period 1901–2008     

Vincent Kint  Wim Aertsen  Matteo Campioli  Dries Vansteenkiste  Andy Delcloo  Bart Muys 《Climatic change》2012,115(2):343-363

Both increasing and decreasing 20th century growth trends have been reported in forests throughout Europe, but only for few species and areas suitable modelling techniques have been used to distinguish individual tree growth (operating on a local scale) from growth change due to exogenous factors (operating on a broad geographical scale). This study relates for the first time observed growth changes, in terms of basal area increment (BAI) of dominant trees of pedunculate oak, common beech and Scots pine, in north-west European temperate lowland forests (Flanders) to climate, atmospheric CO₂ and tropospheric O₃ concentrations, N deposition, site quality and forest structure for more than a century (the period 1901?C2008), applying mixed models. Growth change during the 20th century is observed for oak (increasing growth) and beech (increasing growth until the 1960s, growth decline afterwards), but not for pine. It was possible to relate growth change of oak and beech to climate time series and N deposition trends. Adding time series for CO₂ and O₃ concentration did not significantly improve model results. For oak and beech a switch from positive to negative growth response with increasing nitrogen deposition throughout time is observed. Growth increase for oak is mainly determined by the interaction between growing season temperature and soil water recharge. It is reasonable to assume that the observed growth trend for oak will continue for as long as early season water availability is not compromised. The decreasing trend in summer relative air humidity observed since the 1960s in the study area can be a main cause of recent beech BAI decrease. A further growth decline of beech can be expected, independent of site quality.  相似文献   

Prediction of the thermodynamic properties of metal–chromate aqueous complexes to high temperatures and pressures and implications for the speciation of hexavalent chromium in some natural waters     

Marina Accornero  Luigi Marini  Matteo Lelli 《Applied Geochemistry》2010

Log–log correlation plots between the dissociation constants of known metal–chromate complexes and those of corresponding metal–sulfate complexes at 25 °C, 1 bar were used to derive the standard partial molal Gibbs free energies of formation of unknown metal–chromate complexes involving either (i) monovalent cations, divalent cations, and trivalent lanthanides or (ii) trivalent cations (excluding those of rare earth elements, REE) and tetravalent cations. For each of these two classes of ionic associations, empirical relationships between the standard partial molal volumes, isobaric heat capacities and entropies of known metal–chromate complexes and the corresponding thermodynamic properties of metal ions have been found. These data were utilized to evaluate the solute-characteristic parameters of the revised Helgeson–Kirkham–Flowers equation of state and to compute the thermodynamic properties of the dissociation reactions of metal–chromate complexes at high temperatures and pressures.  相似文献   

Tracing the cosmological assembly of stars and supermassive black holes in galaxies     

Andrea Merloni  Gregory Rudnick  Tiziana Di Matteo 《Monthly notices of the Royal Astronomical Society》2004,354(3):L37-L42

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Hard X-Ray Emission from Elliptical Galaxies and Its Contribution to the X-Ray Background     

Di Matteo T  Allen SW 《The Astrophysical journal》1999,527(1):L21-L24

We explore the implications of the discovery of hard, power-law X-ray sources in the spectra of nearby elliptical galaxies for the origin of the X-ray background (XRB). The spectra of these sources are consistent with models of thermal bremsstrahlung emission from low radiative efficiency accretion flows around central supermassive black holes and are unique in that they approximately match the spectrum of the hard XRB. If such sources, with luminosities consistent with those observed in nearby elliptical galaxies, are present in most early-type galaxies, then their integrated emission may contribute significantly to the XRB. These sources may also contribute to the hard source counts detected in deep X-ray surveys.  相似文献   

HTLP metamorphism and fluid-fluxed melting during multistage anatexis of continental crust (N Sardinia,Italy)     

Leonardo Casini  Matteo Maino  Antonio Langone  Giacomo Oggiano  Stefania Corvò  Joan Reche Estrada  Montserrat Liesa 《Journal of Metamorphic Geology》2023,41(1):25-57

The Variscan high-grade metamorphic basement of northern Sardinia and southern Corsica record lower Carboniferous anatexis related to post-collisional decompression of the orogen. Migmatites exposed in the Punta Bianca locality (Italy) consist of quartz + biotite + plagioclase + K-feldspar orthogneisses, garnet and cordierite-bearing diatexite and metatexites, derived from metasediments. Field evidence, petrographic observations, ELA-ICP-MS zircon and monazite dating and pseudosection modelling suggest that anatexis was apparently episodic involving two main stages of partial melting. Using pseudosection modelling, we infer that the first stage of partial melting is in the upper amphibolite facies (~0.45 GPa at ~740°C). Cordierite overgrowths replacing sillimanite, combined with the composition of plagioclase and K-feldspar, suggest decompression followed cooling below the solidus at low pressures of ~0.3 GPa. The age of the first anatectic event is not precisely constrained because of extensive resetting of the isotopic systems during the second melting stage, yet few zircons preserve a lower Carboniferous age which is consistent with the regional dataset. This lower Carboniferous migmatitic fabric is offset by a network of pseudotachylyte-bearing faults suggestive of cooling to greenschist facies conditions. Garnet/cordierite-bearing diatexites incorporate fragments of pseudotachylite-bearing orthogneiss and metatexites. Pseudosection modelling indicates nearly isobaric re-heating up to ~750°C, followed by further cooling below the solidus. The inferred P–T path is consistent with decompression and cooling of the Variscan crust through post-collisional extension and collapse of the thickened orogenic crust, followed by nearly isobaric re-heating at low pressures (~0.3 GPa) yielding to a second melting stage under LP-HT conditions. U/Th-Pb monazite ages for diatexite migmatites indicate an upper bound of 310–316 Ma for the second melting stage, suggesting that the second melting stage is coincident with the regional phase of crustal shearing. The cause of the high geothermal gradient required for re-heating during the second melting stage is unknown but likely requires some heat source that was probably related to dissipation of mechanical work within crustal-scale shear zones. According to this interpretation, some upper Carboniferous peraluminous granite precursors of the Corsica–Sardinia Batholith could be the outcome rather than the cause of the late-Variscan high-T metamorphism.  相似文献   

Gravitomagnetic field of rotating rings     

Matteo Luca Ruggiero 《Astrophysics and Space Science》2016,361(4):140

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Micromechanical inspection of incremental behaviour of crushable soils     

Ciantia  Matteo O.  Arroyo  Marcos  O’Sullivan  Catherine  Gens  Antonio 《Acta Geotechnica》2019,14(5):1337-1356

In granular soils grain crushing reduces dilatancy and stress obliquity enhances crushability. These are well-supported specimen-scale experimental observations. In principle, those observations should reflect some peculiar micromechanism associated with crushing, but which is it? To answer that question the nature of crushing-induced particle-scale interactions is here investigated using an efficient DEM model of crushable soil. Microstructural measures such as the mechanical coordination number and fabric are examined while performing systematic stress probing on the triaxial plane. Numerical techniques such as parallel and the newly introduced sequential probing enable clear separation of the micromechanical mechanisms associated with crushing. Particle crushing is shown to reduce fabric anisotropy during incremental loading and to slow fabric change during continuous shearing. On the other hand, increased fabric anisotropy does take more particles closer to breakage. Shear-enhanced breakage appears then to be a natural consequence of shear-enhanced fabric anisotropy. The particle crushing model employed here makes crushing dependent only on particle and contact properties, without any pre-established influence of particle connectivity. That influence does not emerge, and it is shown how particle connectivity, per se, is not a good indicator of crushing likelihood.

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Carbon quantity defines productivity while its quality defines community composition of bacterioplankton in subarctic ponds     

Toni Roiha  Marja Tiirola  Matteo Cazzanelli  Milla Rautio 《Aquatic Sciences - Research Across Boundaries》2012,74(3):513-525

Bacterial communities in 16 oligotrophic ponds in Kilpisj?rvi, subarctic Finland, were studied to test the hypothesis that dissolved organic carbon (DOC) quantity and quality differently influence bacterioplankton. The ponds were located below and above treeline at 600?m a.s.l., with 2?C4 fold higher concentration of DOC below treeline. The concentration of DOC changed during the open-water season with highest values measured in mid-summer. Bacterial production, abundance, biomass were highest in mid-summer and correlated positively with the concentration of DOC. Quality indices of DOC showed that spring differed from the rest of the season. Highest specific UV-absorbance (SUVA) and humification index (HI), ratio a250/a265 and lowest fluorescence index (FI) were found during spring compared to summer and autumn, possibly indicating higher relative importance of allochthonous carbon during spring and a seasonal effect of photo-oxidation. According to Length Heterogeneity Polymerase Chain Reaction (LH-PCR) analyses, bacterial communities in spring were significantly different from those later in the season, possible due to the introduction of terrestrial bacteria associated with higher molecular weight material in spring DOC. Comparison between ponds situated above and below treeline revealed that bacteria were more abundant and productive at lower altitudes, which is probably connected to higher concentrations of DOC. The results also suggest that increased temperature and precipitation induced by global change and consequent higher allochthonous DOC runoff from the catchment could have a strong impact on biomass, productivity and community composition of micro-organisms in subarctic ponds and lakes.  相似文献