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Spinterface:A new platform for spintronics

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Nano Materials Science 2019年第3期1卷 149-155页

作者： Ilaria Bergenti Valentin Dediu Institute of Nanostructured Materials ismn National Research Council CNR40129BolognaItaly cnr-ismn Bologna Via P.Gobetti 10140129BolognaItaly

Since its discovery in early 2000’s Molecular Spintronics has developed in an established and fructuous research field,achieving a number of outstanding results and unveiling unusual spintronic *** the most mysterious device element,the interface,in molecular spintronics has on contrary received and enormous attention and even gained a special nickname–the *** on significant efforts of many research groups worldwide it has been established its critical role in defining the main functionalities of molecular spintronic *** the spinterface was found to control the properties of the both components constituting the interface,not only those of the molecular layer but surprisingly also those of the magnetic *** paper aims to overview the most striking spinterface properties and to highlight the possibilities to promote new device paradigms based on interfacial modulation.

关键词： Molecular spintronics Ferromagnetism Spin polarization Hybridization organic semiconductors

Partial oxidation of methane over SiO2 supported Ni and NiCe catalysts

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Journal of Energy Chemistry 2020年第8期29卷 1-9,I0001页

作者： A.Emamdoust V.La Parola G.Pantaleo M.L.Testa S.Farjami Shayesteh A.M.Venezia Nanostructure Lab Department of PhysicsUniversity of GuilanRashtIran Istituto per lo Studio dei Materiali Nanostrutturati(ismn-cnr) Via Ugo La Malfa 153PalermoItaly

Nickel and nickel-ceria catalysts supported on high surface area silica, with 6 wt% Ni and 20 wt% CeO2 were prepared by microwave assisted(co) precipitation method. The catalysts were investigated by XRD,TPR and XPS analyses and they were tested in partial oxidation of methane(CPO). The catalytic reaction was carried out at atmospheric pressure in a temperature range of 400–800℃ with a feed gas mixture containing methane and oxygen in a molecular ratio CH4/O2=2. The Ni catalyst exhibited 60% methane conversion with 60% selectivity to CO already at 500℃. On the contrary, the Ni–Ce catalyst was inert to CPO up to 700℃. Moreover, the former catalyst reproduced its activity at the descending temperatures maintaining a good stability at 600℃, over a reaction time of 80 h, whereas the latter one completely deactivated. Test of CH4 temperature programmed surface reaction(CH4-TPSR) revealed a higher methane activation temperature(> 100℃) for the Ni–Ce catalyst as compared to the Ni one. Noticeable improvement of the ceria containing catalyst occurred when the reaction test started at a temperature higher than the methane decomposition temperature. In this case, the sample achieved the same catalytic behavior of the Ni catalyst. As confirmed by XPS analyses, the distinct electronic state of the supported nickel was responsible for the differences in catalytic behavior.

关键词： Methane catalytic partial oxidation(CPO) Ni catalyst NiCe SiO2 supported catalysts

Density of states characterization of TiO_(2) films deposited by pulsed laser deposition for heterojunction solar cells

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Nano Research 2022年第5期15卷 4048-4057页

作者： Daniele Scire Roberto Macaluso Mauro Mosca Maria Pia Casaletto Olindo Isabella Miro Zeman Isodiana Crupi Department of Engineering University of PalermoViale delle ScienzeEd.9Palermo 90128Italy Institute of Nanostructured Materials(ismn) National Research Council(CNR)Via Ugo La Malfa 153Palermo 90146Italy Photovoltaic Materials and Devices Group Delft University of TechnologyMekelweg 4Delft 2628CDthe Netherlands

The application of titanium dioxide(TiO_(2))in the photovoltaic(PV)field is gaining traction as this material can be deployed in doping-free heterojunction solar cells with the role of electron selective *** modeling-based optimization of such contact,knowledge of the titanium oxide defect density of states(DOS)is *** this paper,we report a method to extract the defect density through nondestructive optical measures,including the contribution given by small polaron optical *** presence of both related to oxygen-vacancy defects and polarons is supported by the results of optical characterizations and the evaluation of previous observations resulting in a defect band fixed at 1 eV below the conduction band edge of the *** cells employing pulsed laser deposited-TiO_(2)electron selective contacts were fabricated and *** J-V curve of these cells showed,however,an S-shape,then a detailed analysis of the reasons for such behavior was carried *** use a model involving the series of a standard cell equivalent circuit with a Schottky junction in order to explain these atypical performances.A good matching between the experimental measurements and the adopted theoretical model was *** extracted parameters are listed and analyzed to shed light on the reasons behind the low-performance cells.

关键词： solar cell heterojunction photovoltaic(PV) defect density small polaron pulsed laser deposition(PLD) titanium dioxide(TiO_(2)) defects

Simplified hydrodynamic models for the analysis of marine propellers in a wake-field

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Journal of Hydrodynamics 2013年第6期25卷 954-965页

作者： DURANTE D. DUBBIOSO G. TESTA C. cnr-INSEAN The Italian Ship Model Basin

This paper presents a comparison among different hydrodynamic models for the analysis of the unsteady loads delivered by a marine propeller working in an axial, non-uniform inflow. Specifically, for a propeller subjected to a wake-field dominated by local high-frequency changes in space, the unsteady hydroloads predicted by the Nakatake formulation are compared with those given by the Theodorsen and Sears theories, respectively. Drawbacks and potentialities of these approaches are highlighted to assess a computationally efficient hydrodynamic solver for the analysis of operating conditions where propeller blades are significantly perturbed by a multi-harmonic onset-flow. Guidelines coming from this investigation may drive the choice of a fast and reliable unsteady propeller modeling that represents a good trade-off between accuracy of simulation and cost of computation within implementation in Computational Fluid Dynamics （CFD） solvers. The hydrodynamic formulations herein proposed are validated through numerical comparisons with the （accurate but computationally expensive） propeller loads predicted by a fully 3-D panel-method Boundary Element Method （BEM） solver, suited for the analysis of propellers operating in a complex hydrodynamic environment.

关键词： actuator disk airfoil theories Boundary Element Method (BEM) hydrodynamics

Can leukocyte telomere shortening be a possible biomarker to track Huntington’s disease progression?

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Neural Regeneration Research 2019年第10期14卷 1709-1710页

作者： Elide Mantuano Martina Peconi Daniela Scarabino cnr Institute of Translational Pharmacology RomeItaly cnr Institute of Molecular Biology and Pathology Rome Italy

Huntington's disease (HD): HD is an autosomal dominant neurodegenerative disease, caused by a CAG trinucleotide repeat expansion in the first exon of the HTT gene encoding the huntingtin protein. The mutant protein contains an expanded polyglutamine sequence that confers a toxic gain-of-function and causes neurodegeneration. Moreover, several studies indicate that loss of the normal protein beneficial functions, contribute to the pathology (Schulte and Littleton 2011). Triplet expansion over 40 repeats are fully penetrant and invariably lead to manifest HD in the fourth or fifth decade of life.

关键词： Huntington's disease(HD) neurodegenerative disease fifth decade of life

Small scale biodiesel synthesis from waste frying oil and crude methanol in Morocco

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Chinese Journal of Chemical Engineering 2016年第9期24卷 1178-1185页

作者： Fatiha Ouanji Marouane Nachid Mohamed Kacimi Leonarda F.Liotta Fabtizio Puleo Mahfoud Ziyad Universite Mohammed V Faculte des SciencesDepartement de ChimieLaboratoire de Physico-chimie des Materiaux et Catalyse(URAC26)Avenue lbn BattoutaBP.1014RabatMorocco Hassan 11 Academy of Sdence and Technology RabatMorocco lstituto per lo Studio dei Materiali Nanostrutturati(ismn)-cnr via Ugo La Malfa15390146 PalermoItaly

Biodiesel was produced at small scale by transesterification of used frying oil（UFO） recovered from Moroccan pastry shops and fish frying restaurants. Biodiesel was first synthesised at laboratory scale in order to optimize the transesterification parameters. The cost of the final product was also optimized using low-cost raw *** UFO and the produced biodiesel were characterized with several techniques including gas chromatography,1H NMR,13 C NMR, FTIR, and TGA–TDA techniques.1H NMR gas chromatographic analyses of the final product confirmed that the transesterification in the chosen experimental conditions was completed. These results were confirmed by TGA–TDA analysis used as new techniques to monitoring triglyceride conversion. The biodiesel did not contain any trace of glycerol, and it did meet the international standards. The transesterification at low cost in small scale conditions was performed at 60 ℃ using 1.2% of KOH and a methanol/oil molar ratio of 6：1. A yield of 80.8% was achieved. The properties of the produced biodiesel were found to be as good as those of biodiesels obeying to European standards. The biodiesel production was also performed at small-scale for individual utilisation. Thus, the product was tested in a kerosene stove for heating and non-modified commercial diesel engine producing electricity.

关键词： Biodiesel Transesterification Small-scale Thermogravimetry

Comparison of PM_(10) concentrations and metal content in three different sites of the Venice Lagoon: An analysis of possible aerosol sources

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Journal of Environmental Sciences 2012年第11期24卷 1954-1965页

作者： Daniele Contini Franco Belosi Andrea Gambaro Daniela Cesari Angela Maria Stortini Maria Chiara Bove Institute of Atmospheric Sciences and Climate ISAC-CNRLecceItaly Institute of Atmospheric Sciences and Climate ISAC-CNRBolognaItaly Department of Environmental Sciences Informatics and StatisticsUniversity Ca'Foscari of VeniceVeneziaItaly Institute of Atmospheric Sciences and Climate ISAC-CNRLecceItaly. Institute for the Dynamics of Environmental Processes IDPA-CNRVeneziaItaly

The Venice Lagoon is exposed to atmospheric pollutants from industrial activities, thermoelectric power plants, petrochemical plants, incinerator, domestic heating, ship traffic, glass factories and vehicular emissions on the mainland. In 2005, construction began on the mobile dams （MOSE）, one dam for each channel connecting the lagoon to the Adriatic Sea as a barrier against high tide. These construction works could represent an additional source of pollutants. PM10 samples were taken on random days between 2007 and 2010 at three different sites： Punta Sabbioni, Chioggia and Malamocco, located near the respective dam construction worksites. Chemical analyses of V, Cr, Fe, Co, Ni, Cu, Zn, As, Mo, Cd, Sb, T1 and Pb in PM10 samples were performed by Inductively coupled plasma- quadrupole mass spectrometry （ICP-QMS） and results were used to identify the main aerosol sources. The correlation of measured data with meteorology, and source apportionment, failed to highlight a contribution specifically associated to the emissions of the MOSE construction works. The comparison of the measurements at the three sites showed a substantial homogeneity of metal concentrations in the area. Source apportionment with principal component analysis （PCA） and positive matrix factorization （PMF） showed that a four principal factors model could describe the sources of metals in PM10. Three of them were assigned to specific sources in the area and one was characterised as a source of mixed origin （anthropogenic and crustal）. A specific anthropogenic source of PM10 rich in Ni and Cr, active at the Chioggia site, was also identified.

关键词： MOdulo Sperimentale Elettromeccanico metals Venice Lagoon PM10 principal component analysis positive matrixfactorization

The measure of friction angles for different types of granular material

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Journal of Mountain Science 2019年第4期16卷 769-777页

作者： DEGANUTTI Andrea Maria TECCA Pia Rosella GENEVOIS Rinaldo cnr-IRPI Department of Geosciences University of Padova

The aim of this research is to deepen the knowledge of the role of friction on the dynamics of granular media; in particular the friction angle is taken into consideration as the physical parameter that drives stability, motion and deposition of a set of grains of any nature and size. The idea behind this work is a question: is the friction angle really that fundamental and obvious physical parameter which rules stability and motion of granular media as it seems from most works which deal with particle dynamics? The experimental study tries to answer this question with a series of laboratory tests, in which different natural and artificial granular materials have been investigated in dry condition by means of a tilting flume. The characteristic friction angles, both in deposition(repose) and stability limit(critical) conditions, were measured and checked against size, shape, density and roughness of the considered granular material. The flume tests have been preferred to "classical" geotechnical apparatuses(e.g. shear box) since the flume experimental conditions appear closer to the natural ones of many situations of slope stability interest(e.g. a scree slope). The results reveal that characteristic friction angles depend on size and shape of grains while mixtures of granules of different size show some sorting mechanism with less clear behaviour.

关键词： Rheology Granular material Friction angle Deposition process Yielding process

Marine propellers performance and flow-field prediction by a free-wake panel method

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Journal of Hydrodynamics 2014年第5期26卷 780-795页

作者： GRECO Luca MUSCARI Roberto TESTA Claudio DI MASCIO Andrea cnr-INSEAN Italian Ship Model BasinRomeItaly cnr-IAC Istituto per le Applicazioni del Calcolo "M. Picone"RomeItaly

A Boundary Element Method （BEM） hydrodynamics combined with a flow-alignment technique to evaluate blades shed vorticity is presented and applied to a marine propeller in open water. Potentialities and drawbacks of this approach in capturing propeller performance, slipstream velocities, blade pressure distribution and pressure disturbance in the flow-field are highlighted by comparisons with available experiments and RANSE results. In particular, correlations between the shape of the convected vortex- sheet and the accuracy of BEM results are discussed throughout the paper. To this aim, the analysis of propeller thrust and torque is the starting point towards a detailed discussion on the capability of a 3-D free-wake BEM hydrodynamic approach to describe the local features of the flow-field behind the propeller disk, in view of applications to propulsive configurations where the shed wake plays a dominant role.

关键词： BEM hydrodynamics free-wake analysis BEM-RANSE comparison