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Green and low temperature synthesis of nanocrystalline transition metal ferrites by simple wet chemistry routes

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Nano Research 2014年第7期7卷 1027-1042页

作者： stefano Diodati Luciano Pandolfo Andrea Caneschi stefano Gialanella Silvia Gross Istituto per I'Energetica e le In terfasi IENI-CNR and INSTM UdR di Padova via Marzolo 11-35131 Padova Italy Dipartimento di Scienze Chimiche Universit& degli Studi di Padova via Marzolo 11-35131 Padova Italy Laboratory of Molecular Magnetism LAMM Dipartimento di Chimica e UdR INSTM di Firenze Polo Scientifico Via della Lastruccia 3 50019 Sesto Fiorentino (FI) Italy Dipartimen to di Ingegneria Industriale Universita degli Studi di Tren to via Mesiano 771-38123 Trento Italy

Crystalline and nanostructured cobalt （CoFe2O4）, nickel （NiFe2O4）, zinc （ZnFe2O4） and manganese （MnFe2O4） spinel ferrites are synthesized with high yields, crystallinity and purity through an easy, quick, reproducible and low-temperature hydrothermal assisted route starting from an aqueous suspension of copredpitated metal oxalates. The use of water as a reaction medium is a further advantage of the chosen protocol. Additionally, the zinc spinel is also prepared through an alternative route combining copredpitation of oxalates from an aqueous solution with thermal decomposition under reflux conditions. The nanocrystalline powders are obtained as a pure crystalline phase already at the extremely low tem- perature of 75 ℃ and no further thermal treatment is needed. The structure and microstructure of the prepared materials is investigated by means of X-ray powder diffraction （XRPD）, while X-ray photoelectron spectroscopy （XPS） and inductively coupled plasma-atomic emission spectroscopy （ICP-AES） analyses are used to gain information about the surface and bulk composition of the samples, respectively, confirming the expected stoichiometry. To investigate the effect of the synthesis protocol on the morphology of the obtained ferrites, transmission electron microscopy （TEM） observations are performed on selected samples. The magnetic properties of the cobalt and manganese spinels are also investigated using a superconducting quantum device magnetometer （SQUID） revealing hard and soft ferrimagnetic behavior, respectively.

关键词： ferrites hydrothermal low temperature wet chemistry green

Next Generation Narrowband(Under 500 kHz) Power Line Communications(PLC) Standards

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China Communications 2015年第3期12卷 1-8页

作者： stefano Galli Thierry Lys ASSIA 333 Twin Dolphin DrRedwood CityCA 94065USA ERDF 345 Avenue G.Clemenceau92000 NanterreFrance

In the past decade,several efforts around the world were started with the goal of introducing "smart metering" capabilities into the power *** efforts have spurred renewed interest in the design of next generation Narrowband Power Line Communications(NB-PLC) *** the past few years,ITU-T and IEEE have standardized a family of next generation OFDM-based NB-PLC transceivers some of which are today being considered for massive deployments in Europe and *** paper addresses the important role that PLC has not only for smart metering but also for many other Smart Grid applications,and also gives an overview of the main differences between these next generation NB-PLC standards.

关键词： power line communications standard smart grid applications

3D aerogels from hybrid 2D materials:ultralight and flexible superinsulators

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National Science Review 2023年第10期10卷 8-9页

作者： stefano Ippolito Yury Gogotsi A.J.Drexel Nanomaterials Institute and Department of Materials Science & Engineering Drexel University

Advances in research and technology to boost human space exploration proceed at a brisk pace,although a major obstacle remains:the cold and empty outer *** we capitalize on the unique properties of specific materials and structures to address this problem?Considered among the best insulating materials available,aerogels have become prime candidates in this field owing to their ultralight weight,large surface area,

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The role of a national park in classifying mountain tourism destinations: An exploratory study of the Italian Western Alps

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Journal of Mountain Science 2019年第7期16卷 1675-1690页

作者： DUGLIO stefano LETEY Marilisa Department of Management University of Torino218 bisCorso Unione Sovietica10134TorinoItaly NatRisk-Research Centre on natural risk in mountain and hilly environments University of TorinoTorinoItaly

Together with the main aim of preserving nature,national parks are also expected to play an important role for the local communities,driving economic activities toward the lens of sustainable *** contribution aims to present an exploratory study on the relationship between the presence of a protected mountain area,the Gran Paradiso National Park(GPNP),in the North West of the Italian Alps,and the classification of tourism destinations,according to Weaver model of destination *** from the model,the authors provide a quantitative analysis using a set of variables and indicators to comprehensively assess the differing patterns assumed by the municipalities within the borders of the GPNP and those that are *** provisional results illustrate that the municipalities within the border of a protected area are more likely to be grouped alongside the sustainable mountain ***,research outcomes confirm that a protected area does not necessarily contrast the tourism industry but instead may boost local development by driving it within the borders of the sustainable development,switching from the area’s only preservation function to a flywheel for the local communities.

关键词： Mountain tourism Sustainable tourism Destination management National park Alps

KIN SP:A boundary element method based code for single pile kinematic bending in layered soil

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第1期10卷 176-187页

作者： stefano Stacul Nunziante Squeglia Department of Civil and Industrial Engineering University of Pisa

In high seismicity areas, it is important to consider kinematic effects to properly design pile *** effects are due to the interaction between pile and soil deformations induced by seismic waves. One of the effect is the arise of significant strains in weak soils that induce bending moments on piles. These moments can be significant in presence of a high stiffness contrast in a soil deposit. The single pile kinematic interaction problem is generally solved with beam on dynamic Winkler foundation approaches(BDWF) or using continuous models. In this work, a new boundary element method(BEM)based computer code(KIN SP) is presented where the kinematic analysis is preceded by a free-field response analysis. The analysis results of this method, in terms of bending moments at the pile-head and at the interface of a two-layered soil, are influenced by many factors including the soil-pile interface discretization. A parametric study is presented with the aim to suggest the minimum number of boundary elements to guarantee the accuracy of a BEM solution, for typical pile-soil relative stiffness values as a function of the pile diameter, the location of the interface of a two-layered soil and of the stiffness contrast. KIN SP results have been compared with simplified solutions in literature and with those obtained using a quasi-three-dimensional(3D) finite element code.

关键词： Kinematic bending KIN SP Discretization Boundary element method(BEM) Pile-soil interaction Soil-structure interaction

Scour process caused by multiple subvertical non-crossing jets

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Water Science and Engineering 2017年第1期10卷 17-24页

作者： stefano Pagliara Michele Palermo DESTEC-Department of Energy SystemsTerritory and Construction EngineeringUniversity of Pisa56122 PisaItaly

The scour process induced by plunging jets is an important topic for hydraulic engineers. In recent decades, several researchers have developed new strategies and methodologies to control the scour morphology, including different jet arrangements and structures located in the stilling basin. It has been found that multiple jets can cause less scouring than single plunging jets. Based on this evidence, this study aimed to investigate the equilibrium morphology caused by multiple non-crossing jets. A dedicated laboratory model was built and experimental tests were carried out under different combinations of jet inclination angles, by varying the tailwater level and the virtual crossing point location, which was set below the original channel bed level. It was experimentally shown that the equilibrium scour morphology depends on the jet discharge, the differences in non-crossing jet inclination angles, the downstream water level, and the distance of the virtual crossing point from the original channel bed level. In particular, the last parameter was found to be one of the most influential parameters, because of the resulting flow patterns inside the water body. Furthermore, the analysis of experimental evidence allowed for a complete and detailed classification of the scour hole typologies. Three different scour typologies were distinguished and classified. Finally, based on previous studies, two novel re-lationships have been proposed to predict both the maximum scour depth and length within a large range of hydraulic and geometric parameters.

关键词： Multiple subvertical jets Plunge pool Scour Spillway Tailwater

Peripheral nerve regeneration research Why is it getting so “cool”?

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Neural Regeneration Research 2012年第29期7卷 2245-2246页

作者： stefano Geuna Neuroscience Institute of the Cavalieri Ottolenghi Foundation (NICO) & Department of Clinical and Biological Sciences University of TurinOrbassano 10043TurinItaly

More than twenty years ago, when I first started working on plasticity and regeneration in the peripheral nervous system, I had the feeling of being part of a little, though lively, scientific community that was rarther isolated in the world of neuroscience which appeared to me as almost only focused on central nervous system. Since then, things have progressively changed very much and, today, interest in the regeneration in the peripheral nervous system, and especially in its main component. Le. the peripheral nerves （Geuna S, Raimondo S, Ronchi G, et al. Histology of the peripheral nerve and changes occurring during nerve regeneration. Int Rev Neurobiol. 2009;87：27-46.）, is sprading tremendouslty among both basic and clinical neuroscientists.

关键词： Peripheral nerve regeneration research Why is it getting so cool

Temperature-and vacancy-concentration-dependence of heat transport in Li_(3)ClO from multi-method numerical simulations

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npj Computational Materials 2022年第1期8卷 197-205页

作者： Paolo Pegolo stefano Baroni Federico Grasselli SISSA—Scuola Internazionale Superiore di Studi Avanzati 34136TriesteItaly CNR-Istituto Officina dei Materiali SISSA34136TriesteItaly COSMO—Laboratory of Computational Science and Modelling IMXÉcole Polytechnique Fédérale de Lausanne1015LausanneSwitzerland

Despite governing heat management in any realistic device,the microscopic mechanisms of heat transport in all-solid-state electrolytes are poorly known:existing calculations,all based on simplistic semi-empirical models,are unreliable for superionic conductors and largely overestimate their thermal *** this work,we deploy a combination of state-of-the-art methods to calculate the thermal conductivity of a prototypical Li-ion conductor,the Li_(3)ClO *** leveraging ab initio,machine learning,and force-field descriptions of interatomic forces,we are able to reveal the massive role of anharmonic interactions and diffusive defects on the thermal conductivity and its temperature dependence,and to eventually embed their effects into a simple rationale which is likely applicable to a wide class of ionic conductors.

关键词： transport conductivity eventually

Range-separated hybrid functionals for accurate prediction of band gaps of extended systems

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npj Computational Materials 2023年第1期9卷 1237-1245页

作者： Jing Yang stefano Falletta Alfredo Pasquarello Chaire de Simulationàl’Echelle Atomique(CSEA) Ecole Polytechnique Fédérale de Lausanne(EPFL)Lausanne CH-1015Switzerland

In this work,we systematically evaluate the accuracy in band gap prediction of range-separated hybrid functionals on a large set of semiconducting and insulating materials and carry out comparisons with the performance of their global *** observe that all the range-separated hybrid functionals that correctly describe the long-range dielectric screening significantly improve upon standard hybrid functionals such as PBE0 and *** choice of the short-range Fock exchange fraction and the screening length can further reduce the predicted *** then propose a universal expression for the selection of the inverse screening parameter as a function of the short-range and long-range Fock exchange fractions,which results in a mean absolute error as small as 0.15 eV for band gap prediction.

关键词： separated functionals exchange