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The method developed in a previous paper [R. Mazo, J. Chem. Phys. 129, 154101 (2008)] for extracting information on the size of relative fluctuations in multicomponent systems is tested on ten binary systems and one ternary system. For the binary systems, it is found that the approximation works well for mole fractions in the range of 0.15–0.85 in most cases. For the ternary case, the method inherently yields less information and is valid only over a more restricted range for the case studied (chloroform-methanol-acetone). It is found that the predicted ratio of number fluctuations is approximately equal to the ratio of molar volumes of the components.

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AbstractThe Law of the Sea and regional and national laws and agreements require exploited populations or stocks to be managed so that they can produce maximum sustainable yields. However, exploitation level and stock status are unknown for most stocks because the data required for full stock assessments are missing. This study presents a new method [abundance maximum sustainable yields (AMSY)] that estimates relative population size when no catch data are available using time series of catch-per-unit-effort or other relative abundance indices as the main input. AMSY predictions for relative stock size were not significantly different from the “true” values when compared with simulated data. Also, they were not significantly different from relative stock size estimated by data-rich models in 88% of the comparisons within 140 real stocks. Application of AMSY to 38 data-poor stocks showed the suitability of the method and led to the first assessments for 23 species. Given the lack of catch data as input, AMSY estimates of exploitation come with wide margins of uncertainty, which may not be suitable for management. However, AMSY seems to be well suited for estimating productivity as well as relative stock size and may, therefore, aid in the management of data-poor stocks.

In the anodisation of Nb in acidic fluoride solutions or warm aqueous alkali, and in that of Mo in concentrated phosphoric acid, impedance spectroscopy provides evidence that 3D film growth proceeds already during the active–passive transition. Indeed, linear potential dependences of both the inverse of the high-frequency capacitance and of the product of the high-frequency resistance times the steady-state current are observed already below the peak potential. Simultaneously, a pseudo-inductive loop at intermediate frequencies is detected in the impedance spectra. In the present paper, we propose a kinetic model for the interpretation of these data. The model assumes that the metal is covered with a non-stoichiometric oxide containing at least two oxidation states of the cation. The processes of oxidative dissolution of the lower valence cations and their transformation to cations of higher valence, leading to passivation, explain the shape of the I–E curve. These processes are limited by both charge transfer at the film–solution (F/S) interface and transport of cation vacancies through the film. Thickening of the oxide film is assumed to proceed simultaneously, and is limited by transport of oxygen vacancies accelerated by an interfacial charge of cation vacancies.

We present the preliminary results of a~230 m deep borehole drilled in the eastern part of the Paganica-San Demetrio-Castelnuovo Basin (PSC) (L'Aquila, central Italy), at the top of the Castelnuovo hill within the Valle Daria paleosurface. The PSC is a NW-SE trending graben bordered by active normal faults and filled by Plio-Quaternary deposits. The oldest ones, largely outcropping in the Valle Daria area, pertain to the San Demetrio-Colle Cantaro Synthem and are composed by several formations, laterally interfingered each other, representing different depositional environments of the Paleolake San Nicandro. The deep lacustrine facies (San Nicandro Fm.-SNF) is formed by laminated to massive whitish calcareous silts, bearing an endemic ostracod assemblage mainly composed by Caspiocypris ssp., allowing to ascribe the SNF to a late Piacenzian-Gelasian age. The outcropping part of the SNF, usually less than 50 m thick, shows a normal magnetic polarity in the basal 10 m, passing upwards to a reverse polarity. In addition, in the upper portion of the SNF, close to Castelnuovo village, three blackish tephra layers are present. Starting from these premises, the Castelnuovo deep borehole (CN1) was realized to investigate, in a palaeoenvironmental and palaeoclimatic perspective, the early sedimentary infilling of the PSC and the evolution of the lacustrine system. The borehole reached a depth of 229.30 m b.g.l., drilling a succession mainly composed by cyclic alternations of fine-grained laminated and massive sediments. The cyclic variations of different parameters among which the CaCO3 content, the granulometry, the sediment colour and the magnetic susceptibility testify that sedimentation was controlled by orbital and climatic oscillations. In detail, the upper part of the well-log (<60 m), partly matching the outcropping succession, is characterized by the typical features of the SNF, consisting of a cyclic alternation of white calcareous silts and light grey clayey-silts couplets, often separated by a thin oxidized silty-sandy layer. In this interval, the CaCO3 content cyclically ranges between 50% and 90%, mostly occurring as lacustrine endogenic calcite. Between 60 and 115 m, clayey levels become more abundant and thicker and organic-rich clay levels appear, whereas minima CaCO3 contents are periodically recorded, around 25%. From 115 to 150 m, massive over-consolidated organic-rich clays are predominant, while calcareous silty levels become occasional and thin. From 150 to 190 m the sequence is formed by alternations of clayey-silts and whitish calcareous silts, while down to 220 m it is composed by alternations of clay and clayey-gravels, with coarser sediments becoming more and more frequent. Below 220 m, fine grain deposits almost disappear, passing to coarse calcareous breccias with rare clayey-silty layers. Several tephra layers are present between 25-30 m, 55-75 m, 100-105 m and 165-170 m. Ongoing analyses, consisting in a multidisciplinary approach that integrates sedimentology, micropaleontology, palynology, tephrochronology, geochemistry and magnetostratigraphy, will constrain the onset and subsequent evolution of the San Nicandro lacustrine system, unraveling the late Pliocene-early Pleistocene climatic variations in the central Mediterranean area and bringing new insights on the post-orogenic evolution of the central Apennines.

Sul mercato esistono molti materiali adsorbenti (prevalentemente a base di carboni attivi eventualmente impregnati, zeoliti, alcuni ossidi metallici) per la desolforazione e la rimozione di VOC anche a temperatura e pressione ambiente. Tuttavia questi materiali mostrano capacità relativamente basse e/o cinetiche di cattura lente a temperatura ambiente, che inevitabilmente si traducono nella necessità di utilizzare grandi volumi di impianto. La ricerca svolta dall'IRC-CNR Napoli e DSC-UNINA, in stretta collaborazione, parte dalla considerazione che lo sviluppo di nuovi materiali e processi ad alta efficienza per la desolforazione (in particolare attraverso adsorbimento) rappresenta un traguardo cruciale per l'impiego vantaggioso di una fonte energetica rinnovabile e residuale quale il biogas, anche su piccola scala in un'ottica di generazione distribuita di energia. La ricerca è stata indirizzata allo sviluppo di materiali adsorbenti ad alte prestazioni e basso costo in grado di far fronte a condizioni operative assai diversificate in termini di temperature (già a partire da temperatura ambiente) e composizioni dei gas da trattare (es. presenza di altri inquinanti).

The modern Common Rail Diesel engine are, normally, optimised for being fuelled with the commercial Diesel fuel. The ECU calibrations are, consequently, defined to obtain the correct compromise between performances and emissions. It is, so, clear that if the engine is fuelled with an alternative bio-fuel with different characteristics (net heating value, stoichiometric A/F ratio, density, viscosity, etc.) the calibration must be modify. Interest in fuels from renewable sources and their use in transport has grown over the last decade. This is because of their biodegradability, potential improvements in exhaust emissions and benefits on the virtuous CO2 cycle of the earth. This paper demonstrates that it is possible to optimise the emissions and the performances of a light duty diesel C.R. engine fuelled with a vegetable derived fuel (Rapeseed Methyl-Ester) pure or blended with commercial Diesel fuel. Particularly in this paper the experimental results and the ECU control solutions referring to different fuel compositions are shown.