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Materials Sciences and Applications 2024年第4期15卷 53-65页

作者： Francesco Rosalbino Giorgio Scavino Graziano Ubertalli dipartimento di scienza Applicata e tecnologia (diSAT) Politecnico di Torino Torino Italy

The influence of sodium silicate on the corrosion behaviour of aluminium alloy 7075-T6 in 0.1 M sodium chloride solution was studied by open circuit potential (OCP) and electrochemical impedance spectroscopy (eIS) techniques. Scanning electron microscopy (SeM) was used to characterize the AA7075-T6 surface. Silicate can significantly reduce corrosion deterioration and the inhibition efficiency increases with the concentration of Na2SiO3. The corrosion inhibition mechanism involves the formation of a protective film over the alloy surface by adsorption of aluminosilicate anions from solution, as has also been suggested by others in literature.

关键词： Aluminium Alloy 7075-T6 Silicate Sodium Chloride electrochemical Impedance Spectroscopy (eIS) Scanning electron Microscopy (SeM)

Quinpi:Integrating Conservation Laws with CWeNO Implicit Methods

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Communications on Applied Mathematics and Computation 2023年第1期5卷 343-369页

作者： G.Puppo M.Semplice G.Visconti dipartimento di Matematica UniversitàLa SapienzaP.le Aldo Moro500185 RomaItaly dipartimento di scienza e alta tecnologia Universitàdell'InsubriaVia Valleggio1122100 ComoItaly

Many interesting applications of hyperbolic systems of equations are stiff,and require the time step to satisfy restrictive stability *** way to avoid small time steps is to use implicit time *** integration is quite straightforward for first-order *** order schemes instead also need to control spurious oscillations,which requires limiting in space and time also in the linear *** propose a framework to simplify considerably the application of high order non-oscillatory schemes through the introduction of a low order implicit predictor,which is used both to set up the nonlinear weights of a standard high order space reconstruction,and to achieve limiting in *** this preliminary work,we concentrate on the case of a third-order scheme,based on diagonally implicit Runge Kutta(diRK)integration in time and central weighted essentially non-oscillatory(CWeNO)reconstruction in *** numerical tests involve linear and nonlinear scalar conservation laws.

关键词： Implicit schemes essentially non-oscillatory schemes Finite volumes WeNO and CWeNO reconstructions

One-and Multi-dimensional CWeNOZ Reconstructions for Implementing Boundary Conditions Without Ghost Cells

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Communications on Applied Mathematics and Computation 2023年第1期5卷 143-169页

作者： M.Semplice e.Travaglia G.Puppo dipartimento di scienza e alta tecnologia Universitàdell'InsubriaVia Valleggio1122100 ComoItaly dipartimento di Matematica Universitàdi TorinoVia C.Alberto1010124 TorinoItaly dipartimento di Matematica UniversitàLa SapienzaP.le Aldo Moro500185 RomaItaly

We address the issue of point value reconstructions from cell averages in the context of third-order finite volume schemes,focusing in particular on the cells close to the boundaries of the *** fact,most techniques in the literature rely on the creation of ghost cells outside the boundary and on some form of extrapolation from the inside that,taking into account the boundary conditions,fills the ghost cells with appropriate values,so that a standard reconstruction can be applied also in the boundary *** Naumann et al.(***.325:252–***://***/10.1016/***.2017.12.041,2018),motivated by the difficulty of choosing appropriate boundary conditions at the internal nodes of a network,a different technique was explored that avoids the use of ghost cells,but instead employs for the boundary cells a different stencil,biased towards the interior of the *** this paper,extending that approach,which does not make use of ghost cells,we propose a more accurate reconstruction for the one-dimensional case and a two-dimensional one for Cartesian *** several numerical tests,we compare the novel reconstruction with the standard approach using ghost cells.

关键词： High-order finite volume schemes Boundary conditions without ghost cells Hyperbolic systems CWeNOZ reconstruction Adaptive order reconstructions

Acid-mediated decarboxylative C–H coupling between arenes and O-allyl carbamates

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Organic Chemistry Frontiers 2022年第6期9卷 1711-1718页

作者： Camilla Loro Julie Oble Francesca Foschi Marta Papis egle MBeccalli Sabrina Giofrè Giovanni Poli Gianluigi Broggini dipartimento di scienza e alta tecnologia Universitàdegli Studi dell’Insubriavia Valleggio 922100 ComoItaly Sorbonne Université Facultédes Sciences et IngénierieCNRSInstitut Parisien de Chimie MoléculaireIPCM4 place Jussieu75005 ParisFrance diSFARM Sezione di Chimica Generale e Organica“A.Marchesini”Universitàdegli Studi di Milanovia Venezian 2120133 MilanoItaly

Treatment of O-allyl N-tosyl carbamates with aromatic compounds in the presence of Cu(OTf)_(2) or TMSOTf as promoters affords N-substituted 1-arylpropan-2-amines,1,2-diarylpropanes,1,1-diarylpropanes,or indanes,depending on the nature of the promoter and of the aryl substrates.A full mechanistic rational allowing appreciation of the outcome of these novel C–H based cascades is *** initial acid promoted decarboxylative/deamidative Friedel–Crafts allylation takes *** protonation of the allylated arene,evolution of the resulting cation may follow different paths depending on the nature of the arene partner and of the allyl moiety in the carbamate.

关键词： allyl moiety coupling

Ultralong and Mesoporous ZnO and γ-Al_2O_3 Oriented Nanowires Obtained by Template-assisted Hydrothermal Approach

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Journal of Materials Science & Technology 2014年第12期30卷 1167-1173页

作者： Carminna Ottone Vivian Farías Rivera Marco Fontana Katarzyna Bejtka Barbara Onida Valentina Cauda Center for Space Human Robotics Polito Istituto Italiano di Tecnologia Corso Trento 21 Turin Italy dipartimento di scienza Applicata e tecnologia (diSAT) Politecnico di Torino Corso Duca Degli Abruzzi 24 Turin Italy

Highly mesoporous Zn O and g-Al2O3nanowires（NWs） are both synthesized by a hydrothermal method using commercially available porous anodic aluminium oxide（AAO） as template. AAO membrane acts as template for Zn O NWs and both as template and precursor for g-Al2O3 NWs. The formation of intermediate phases of porous Zn6Al2（OH）16CO3and boehmite（g-Al OOH） were observed, both occurring during the hydrothermal synthesis of porous Zn O and g-Al2O3 NWs, respectively, and disappearing after annealing at 600 C. This novel template-assisted hydrothermal process leads to the formation of porous Zn O and g-Al2O3NWs（specific surface area of 192 m2 g 1and 263 m2 g 1, respectively）, showing pore sizes around 4 nm in diameter. The influence of the reaction parameters on the nanostructure morphology was also investigated. A Zn O seed layer, deposited on the AAO channels prior to the hydrothermal synthesis, leads to more compact Zn O nanowires（99 m2 g-1） protecting the AAO host from the chemical attack of the precursor solution.

关键词： Mesoporous ZnO nanowires Mesoporous γ-Al2O3 nanowires Boehmite Template-assisted method Hydrothermal synthesis

electromagnetic chirality induced by graphene inclusions in multilayered metamaterials

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Photonics Research 2014年第5期2卷 121-125页

作者： Carlo Rizza elia Palange Alessandro Ciattoni dipartimento di scienza e alta tecnologia Universitàdell’Insubriavia Valleggio 1122100 ComoItaly Consiglio Nazionale delle Ricerche CNR-SPIN67100 Coppito L’AquilaItaly dipartimento di Scienze fisiche e chimiche Universitàdi L’Aquilavia Vetoio67100 Coppito L’AquilaItaly

We theoretically investigate the electromagnetic response of a novel class of multilayered metamaterials obtained by alternating graphene sheets and dielectric layers,the whole structure not exhibiting a plane of reflection symmetry along the stacking *** show that the electromagnetic response of the structure is characterized by a magneto-electric coupling described by an effective chiral *** the intrinsic tunability of graphene–light coupling,we prove that one can tune both the dielectric and the chiral electromagnetic response by varying the graphene chemical potential through external voltage gating.

关键词： parameter. dielectric chiral

Predicting wild boar damages to croplands in a mosaic of agricultural and natural areas

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Current Zoology 2014年第2期60卷 170-179页

作者： Gentile Francesco FICeTOLA Anna BONARdi Paola MAIROTA Vincenzo LeRONNI emilio PADOA-SCHIOPPA dipartimento di Scienze dell'Ambiente e del Territorio e di Scienze delia Terra Universith degli Studi di Milano-Bicocca. Piazza della Scienza 1 20126 Milano Italy dipartimento di Scienze Agro-Ambientali e Territoriali University of Bari Bari.

Crop damages by wildlife is a frequent form of human-wildlife conflict. Identifying areas where the risk of crop damages is highest is pivotal to set up preventive measures and reduce conflict. Species distribution models are routinely used to predict species distribution in response of environmental changes. The aim of this paper was assessing whether species distribution models can allow to identify the areas most at risk of crop damages, helping to set up management strategies aimed at the mitigation of human-wildlife conflicts. We obtained data on wild boarSus scrofadamages to crops in the alta Murgia National Park, Southern Italy, and related them to landscape features, to identify areas where the risk of wild boar damages is highest. We used Maxent to build species distribution models. We identified the spatial scale at which landscape mostly affects the distribution damages, and optimized the regularization parameter of models, through an information-theoretic approach based on AIC. Wild boar damages quickly increased in the period 2007-2011; cereals and legumes were the crops more affected. Large areas of the park have a high risk of wild boar damages. The risk of damages was related to low cover of urban areas or olive grows, intermediate values of forest cover, and high values of shrubland cover within a 2-km radius. Temporally independent validation data demonstrated that models can successfully predict damages in the future. Species distribution models can accurately identify the areas most at risk of wildlife damages, as models calibrated on data collected during only a subset of years correctly predicted damages in the subsequent year.

关键词：野猪预测自然区域马赛克森林覆盖率分布模型野生动物物种分布

efficient hexane isomers separation in isoreticular bipyrazolate metal-organic frameworks:The role of pore functionalization

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Nano Research 2021年第2期14卷 532-540页

作者： Rebecca Vismara Corrado di Nicola Rodrigo Gil-San Millan Kostiantyn V.Domasevich Claudio Pettinari Jorge A.R.Navarro Simona Galli dipartimento di scienza e alta tecnologiay University delVInsubria 22100 ComoItaly School of Science and Technology University ofCamerino62032 Camerino(MC)Italy Departamento de Quimica Inorganica Universidad de Granada18071 GranadaSpain Taras Shevchenko National University of Kyiv 01601 KyivUkraine School of Pharmacy University of Camerino62032 Camerino(MC)Italy Istituto di Chimica dei Composti Organometallici(ICCOM-CNR) 50019 Sesto FiorentinoItaly Consorzio Interuniversitario Nazionale per la scienza e tecnologia dei Materiali 50121 FirenzeItaly Department of Chemistry University of LiverpoolLiverpool L73NYUK

Hydrocarbons separation in petrochemical industries is a key,energy-consuming stage in the manufacture of high-quality added-value products—hence the need for more efficient materials and environmentally friendly methodologies to improve this *** this context,we have studied the effect of metal-organic frameworks(MOFs)pore functionalization in hexane isomers separation,isolating the robust isoreticular zinc(ll)bipyrazolates Zn(BPZ),showing no pore decoration,Zn(Me_(2)BPZ),the pores of which are decorated with apolar methyl groups,and Zn(BPZ(NH_(2))_(2)),the spacers of which possess polar Lewis-basic functions(H_(2)BPZ=1H,1'H-4,4'-bipyrazole;H_(2)Me_(2)BPZ=3,3'-dimethyl-1H,1'H-4,4'-bipyrazole;H_(2)BPZ(NH_(2))_(2)=3,5-diamino-1H,1'H-4,4'-bipyrazole;DMF=dimethylformamide).After characterizing Zn(BPZ(NH_(2))_(2))as per its crystal structure and thermal behaviour,and all the three MOFs as per their textural properties,we investigated,from the experimental and computational points of view,the impact of the square one-dimensional channels decoration on the separation of the hexane isomers,demonstrating the relevance of pore constrictions in the resolution of the title alkanes mixture.

关键词： adsorption molecular sieving nitrogen-donor ligands gas separation pow der diffraction variable-tem perature pulse gas chromatography

Rhynchophorus ferrugineus attack affects a group of compounds rather than rearranging Phoenix canariensis metabolic pathways

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Journal of Integrative Plant Biology 2016年第4期58卷 388-396页

作者： Antonio Giovino Federico Martinelli Sergio Saia Consiglio per la Ricerca in Agricoltura e l'analisi dell'economia agraria(CReA) Unita di ricerca per il recupero e la valorizzazione delle Specie Floricole Mediterranee(CREA-SFM)90011 Bagheria(PA)Italy dipartimento di Scienze Agrarie e Forestali(SAF) University of PalermoViale delle ScienzeEdif.490128 PalermoItaly Istituto euromediterraneo di scienza e tecnologia(IeMeST) Via E.Amari 12390139 PalermoItaly

The red palm weevil（RPW; Rhynchophorus ferrugineus） is spreading worldwide and severely harming many palm species. However, most studies on RPW focused on insect biology, and little information is available about the plant response to the attack. In the present experiment, we used metabolomics to study the alteration of the leaf metabolome of Phoenix canariensis at initial（1^（st） stage） or advanced（2^（nd） stage）attack by RPW compared with healthy（unattacked） *** leaf metabolome significantly varied among treatments. At the 1^（st） stage of attack, plants showed a reprogramming of carbohydrate and organic acid metabolism; in contrast, peptides and lipid metabolic pathways underwent more changes during the 2^（nd） than 1^（st） stage of attack. enrichment metabolomics analysis indicated that RPW attack mostly affected a particular group of compounds rather than rearranging plant metabolic pathways. Some compounds selectively affected during the 1^（st） rather than 2^（nd） stage（e.g. phenylalanine; tryptophan; cellobiose;xylose; quinate; xylonite; idonate; and iso-threonate; cellobiotol and arbutine） are upstream events in the phenylpropanoid,terpenoid and alkaloid biosynthesis. These compounds could be designated as potential markers of initial RPW attack. However,further investigation is needed to determine efficient early screening methods of RPW attack based on the concentrations of these molecules.

关键词： early detection Mediterranean environment metabolomics palms plant borer

High-temperature dynamic behavior in bulk liquid water： A molecular dynamics simulation study using the OPC and TIP4P-ew potentials

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Frontiers of physics 2018年第1期13卷 25-39页

作者： Andrea Gabrieli Marco Sant Saeed Izadi Parviz Seifpanahi Shabane Alexey V. Onufriev Giuseppe B. Suffritti dipartimento di Chimica e Farmacia Universita degli Studi di Sassari Via Vienna 2 07100 Sassari Italy Department of Biomedical engineering and Mechanics Virginia Tech Blacksburgl VA 24060 USA Department of Physics Virginia Tech Blacksburg VA 24060 USA Departments of Computer Science and Physics Virginia Tech Blacksburg VA 24060 USA Consorzio Interuniversitario Nazionale per la scienza e tecnologia dei Materiali (INSTM) Unita di ricerca di Sassari Via Vienna 2 07100 Sassari Italy

Classical molecular dynamics simulations were performed to study the high-temperature （above 300 K） dynamic behavior of bulk water, specifically the behavior of the diffusion coefficient, hydrogen bond, and nearest-neighbor lifetimes. Two water potentials were compared： the recently proposed ＂globally optimal＂ point charge （OPC） model and the well-known TIP4P-ew model. By considering the Arrhenius plots of the computed inverse diffusion coefficient and rotational relaxation constants, a crossover from Vogel-Fulcher-Tammann behavior to a linear trend with increasing temperature was detected at T＊ ≈ 309 and T＊ ≈ 285 K for the OPC and TIP4P-ew models, respectively. experimen- tally, the crossover point was previously observed at T＊ ≈ 315 ±5 K. We also verified that for the coefficient of thermal expansion αp（T, P）, the isobaric αp（T） curves cross at about the same T＊ as in the experiment. The lifetimes of water hydrogen bonds and of the nearest neighbors were evaluated and were found to cross near T＊, where the lifetimes are about 1 ps. For T 〈 T＊, hydrogen bonds persist longer than nearest neighbors, suggesting that the hydrogen bonding network dominates the water structure at T 〈 T＊, whereas for T 〉 T＊, water behaves more like a simple liquid. The fact that T＊ falls within the biologically relevant temperature range is a strong motivation for further analysis of the phenomenon and its possible consequences for biomolecular systems.

关键词： dynamic crossover molecular dynamics bulk liquid water water models