Simulation of growth of Ni-Zr interfacial amorphous regions under nonequilibrium conditions

We have simulated the response of an interfacial amorphous region formed between nickel and zirconium lattices upon temperature increase or the application of uniaxial load by means of molecular-dynamics simulation of a model system based on an n-body potential. The behavior of the amorphous region has been investigated as a function of the load intensity and duration. The system reacts upon uniaxial load application with the growth of the amorphous interface. This has been related to the structural change occurring in the glassy region in the form of a density variation consequent to the introduction of excess free volume. These findings are qualitatively consistent with the current hypothesis invoked to explain diffusion and growth of interfacial amorphous regions formed upon load application on bulk diffusion couples

GIS-Based Geopedological Approach for Assessing Land Suitability for Chestnut (Castanea sativa Mill.) Groves for Fruit Production

The identification of mountainous areas suitable for chestnut stands for fruit production (CSFP) is raising increasing interest among researchers. This work aimed to (i) identify the areas suitable for CSFP shown in a land suitability map easy to read by land planners, and (ii) propose a remote-sensing-based methodology able to identify the lands currently under cultivation for CSFP. This study was conducted using the QGIS software for the Municipality of Castel del Rio, Emilia-Romagna Region, Italy. To obtain the land suitability map, topographic, lithological, and pedological data were acquired, and the areas located between 200 and 1000 m of altitude, with north exposition, a slope < 20°, sandstone-based lithology, and soils with dystric features were selected. The currently cultivated areas for CSFP were identified through remote-sensing images of the early spring period, which were delineated and georeferenced. The findings showed that only 10% of the whole study site area can be considered suitable for CSFP. Further, most of the currently cultivated CSFP (59%) are in non-suitable areas characterised by high slope gradients. The methodology applied in this study can easily provide detailed information about the suitable areas for CSFP and the areas currently cultivated with chestnut, thus allowing accurate land-use planning and land conservation

Preface: NanoItaly 2015

Recent technological and scientific advancements are more and more often related to the nano world, which may refer to the used materials, the designed structures, the involved composites, the machining processes, and/or the realized devices. Indeed, nanotechnologies are triggering a broad number of applications which are suggested by the amazing and unpreceded properties of these new classes of materials, composites, and devices. While academy of scientists and the world of “pure” research have been undoubtedly already fascinated by the great beauty…of nano (U. Fascio), however, a certain inertia and skepticisms still affect some field of industry. This cautious attitude may be partially attributed to some worries of the final consumer, especially in fields like food and nutrition, as well as to a certain incapacity of a part of the academic world to transfer their enthusiasm for their discoveries to the industry and to clearly show how nanotechnologies may improve the quality of our everyday life. Aiming at filling the gap between science and industry, NanoItaly represents a forum where Research and Market can meet each other. The first edition of this forum, NanoItaly 2015, took place from 20 to 23 September 2015, hosted by the Faculty of Civil and Industrial Engineering of SAPIENZA University of Rome. In the suggestive Renaissance Cloister by Giuliano da Sangallo, NanoItaly 2015 alternated exhibitions, plenary sessions, keynote lectures, tutorial sessions, and parallel symposia focused on specific scientific and technological themes. Among the latter: nanosensors and diagnostics; aerogels; microscopy, nanotomography and nanocharacterization techniques; graphene; nano-bio-photonics; nanotribology; nanomedicine and biomedical applications; nanotoxicology; nanotechnologies for cultural heritage, sport, and textile; molecular dynamics and atomistic simulation; nanotechnology and agro-food; nanoelectronics; nanofluidics; optical devices. This volume is a collection of contributions presented at NanoItaly 2015, which however can give only a partial account of the variety of the themes addresses in the different symposia. The articles here collected focus among the others on nanomaterials for catalysis, drug delivery, electronics, and construction industry, imaging and nanocharacterization techniques, and nanofabrication. The Editors are deeply in debt with all the Authors for their valuable contributions, which offer the Reader a significant, albeit pale, overview of the richness of the contents of NanoItaly 2015, and to all the Reviewers for their essential work of revision, fulfilled with carefulness and patience

Microstructural and Kinetic Evolution of Fe Doped MgH2 during H2 Cycling

The effect of extended H2 sorption cycles on the structure and on the hydrogen storage performances of MgH2 powders with 5 wt% of Fe particle catalyst is reported. MgH2 powders with and without Fe have been ball milled under Argon, the doped MgH2 nanocomposite has been cycled under hydrogen pressure up to a maximum of 47 desorption and absorption cycles at 300 °C. After acceleration during the first 10 cycles, the kinetics behavior of doped MgH2 is constant after extended cycling, in terms of maximum storage capacity and rate of sorption. The major effect of cycling on particle morphology is the progressive extraction of Mg from the MgO shell surrounding the powder particles. The Mg extraction from the MgO shell leaves the catalyst particles inside the hydride particles. Many empty MgO shells are observed in the pure ball milled MgH2 upon cycling at higher temperature, suggesting that this enhancement of the extraction efficiency is related to the higher operating temperature which favors Mg diffusivity with respect to the H ion one

Magnetic properties of nanoparticle La0.7Ca0.3MnO3 prepared by glycine-nitrate method without additional heat treatment

Nanoparticle La0.7Ca0.3MnO3 was synthesized for the first time by the glycine-nitrate method without additional heat treatment. The average crystallite size of similar to 10 nm obtained by both transmission electron microscopy and X-ray diffraction was among the smallest achieved by the combustion method. Magnetic measurements showed para-to-ferromagnetic transition temperature T-C = 120 K, saturation magnetization M-S = 46 emu g(-1) and transition of the spin-glass type at T-f = 95 K. (C) 2008 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved

Electron Microscopy Investigation on the Effect of Plastic Deformation in the Alloying of the Immiscible System Cu-Fe

The first steps of the solid state reaction between Cu and Fe induced by plastic deformation at low temperature have been studied by Transmission Electron Microscopy (TEM), X-Ray Diffraction (XRD) and Differential Scanning Calorimetry (DSC). Despite the positive enthalpy of mixing, plastic deformation induces interdiffusion in this system as evidenced by XRD and DSC analysis. TEM observations of samples prepared in different ways show the presence of some Fe into the Cu matrix, a relatively low density of dislocations, a large concentration of small agglomerates of point defects and a well-defined grain shape, suggesting that some dynamic recrystallization occurs during deformation. Considering the low processing temperature we advance the hypothesis that the excess concentration of point defects induced by the high strain rate plastic deformation can provide the necessary atomic mobility. Moreover the role played by these defects on the thermodynamic driving force of the alloying process is considered

ELEMENTI IN TRACCIA E ISOTOPI DELLO Sr E DEL Nd NEGLI ESTRATTI D’AQUA REGIA PER UNA VALUTAZIONE DELL’INQUINAMENTO IN SUOLI URBANI E AGRICOLI DI RAVENNA (ITALIA)

Sr/Ca ratios, and Sr and Nd isotopes, were determined in aqua regia extracts from three urban and agricultural soils from Ravenna. Sr/Ca ratios suggested preferential retention of Sr in the agricultural soils during the weathering of bedrock minerals. Despite of the different land use, the three soils displayed similar isotopic ranges, suggesting common sources for the two elements, likely represented by old marine carbonates and crustal silicates. The Nd isotopes of the urban park topsoil suggest some contamination by the soot of car exhausts.Les rapports Sr/Ca et les isotopes du Sr et du Nd ont été déterminés dans les extraits avec aqua regia de trois sols agricoles et résidentiels dans la zone de Ravenne. Les rapports Sr/Ca suggèrent la rétention préférentielle du Sr dans les sols agricoles pendant l’altération des minéraux. Nonobstant leur utilisation différente, les sols ont des valeurs isotopiques semblables, qui suggèrent des sources communes pour les deux éléments, représentées par d’anciens carbonates marins et des silicates de la croûte terrestre. Les horizons, les plus superficiels du sol du parc urbain sont probablement affectés par une pollution de Nd dérivé des émissions de voitures.Sono stati determinati i rapporti Sr/Ca e i rapporti isotopici di Sr e Nd in estratti di aqua regia di tre suoli interessati da uso agricolo e residenziale della zona di Ravenna. I rapporti Sr/Ca suggeriscono la ritenzione preferenziale dello Sr nei suoli agricoli durante l’alterazione dei minerali. Nonostante il differente uso, i suoli hanno rapporti isotopici simili, suggerendo che Sr e Nd derivano da  sorgenti comuni, rappresentate da carbonati marini antichi e silicati crostali. Gli orizzonti più superficiali del suolo del giardino pubblico mostrano una probabile presenza di Nd derivato dalle emissioni di scarico dei veicoli

Hydrogen Desorption from MgH2 Based Nano-Micro Composites

The microstructure and hydrogen sorption behaviour of MgH2 based nano-hydrides with different additives prepared by ball milling and inert gas condensation has been investigated by XRD, Differential Scanning Calorimetry and Mechanical Spectroscopy. Preliminary results on materials with similar composition and different nanostructures show that suitable mechanical processing and additive additions induce in the nanostructured composites tailored channels for improved ab/de-sorption kinetics at reduced temperature

Hydromorphic to subaqueous soils transitions in the central Grado lagoon (Northern Adriatic Sea, Italy)

The Grado lagoon is among the largest in the Mediterranean sea and is characterized by salt marshes, where tides influenced the development of a complex micromorphology coupled to a micromosaic of vegetation covers. This study represents the first contribution to the understanding of the main processes governing formation, development and spatial transitions between hydromorphic and subaqueous soils in an Adriatic lagoon ecosystem. Physicochemical characteristics and development of soils were investigated in three salt marshes differing for their proximity to the open sea, textural composition and age of formation. Soils of back barrier salt marshes had A/C profiles and were mostly characterized by a sandy coarse texture that allows rapid drainage and subsurface oxygen exchanges. Soil sequences from the inner salt marsh to its submerged border slope or to a brackish waterhole do not simply represent a hydrosequence, but also reflect erosion/sorting/accumulation processes. The soils in the central part of the lagoon have finer texture and in displayed transition or cambic horizons. Silty clay loam textures and low positions allowed the development of more severe anoxic conditions and accumulation of sulphides. The tide oscillation strongly contributed to formation of redoximorphic features, intensity of anaerobic conditions but also colonization by different plant communities. Discriminant analysis was performed to identify physicochemical properties which discriminate the different soils according to geo-morphological position and prevailing plants. It confirmed that differentiation of plant communities occurred according to distinct morphological and hysicochemical soil properties, but also acted as a primary affecting factor of pedogenesis