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催化学报 2011年第11期32卷 1663-1666页

作者： paolo ZUCCA Antonio RESCIGNO Enrico SANJUST Dipartimento di Scienze e Tecnologie Biomediche Università di Cagliari Monserrato 09042 Italy Consorzio per lo Sviluppo dei Sistemi a Grande Interfase Sesto Fiorentino 50019 Italy

A synthetic metalloporphine was immobilized onto a PVA-based and mercapto-grafted solid support, emulating the active site of cytochrome P450. Its ligninolytic peroxidase-like catalytic activity was studied. The coordinated mercapto ligand significantly affected the catalytic features of the catalyst because the oxidation of lignin-model compounds was very slow by comparison with imidazoleand pyridine-coordinated immobilized metalloporphines. Conversely, the catalyst efficiently bleached several industrial dyes and thus demonstrated promising activity for this application. Based on this altered substrate specificity the oxygen-donor catalytic route seems to be more favorable than a single electron oxidation pathway.

关键词： porphine porphyrin lignin peroxidase cytochrome P450 biomimetic

Vibration suppression of speed-controlled robots with nonlinear control

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Frontiers of Mechanical Engineering 2016年第2期11卷 204-212页

作者： paolo BOSCARIOL Alessandro GASPARETTO Dipartimento Politecnico di Ingegneria e Architettura (DPIA) University of Udine Via delle Scienze 206 Udine 33100 Italy

In this paper, a simple nonlinear control strategy for the simultaneous position tracking and vibration damping of robots is presented. The control is developed for devices actuated by speed-controlled servo drives. The conditions for the asymptotic stability of the closed-loop system are derived by ensuring its passivity. The capability of achieving improved trajectory tracking and vibration suppression is shown through experimental tests conducted on a three-axis Cartesian robot. The control is aimed to be compatible with most industrial applications given the simplicity of implementation, the reduced computational requirements, and the use of joint position as the only measured signal.

关键词： industrial robot nonlinear control vibrationdamping model-free control motion control

LEBESGUE DECOMPOSITION AND BARTLE-DUNFORD-SCHWARTZ THEOREM IN PSEUDO-D-LATTICES

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Acta Mathematica Scientia 2013年第3期33卷 653-677页

作者： Anna AVALLONE paolo VITOLO Dipartimento di Matematica e Informatica Università della BasilicataViale dell'Ateneo Lucano 10 85100 Potenza Italy

Let L be a pseudo-D-lattice. We prove that the exhaustive lattice uniformities on L which makes the operations of L uniformly continuous form a Boolean algebra isomorphic to the centre of a suitable complete pseudo-D-lattice associated to L. As a consequence, we obtain decomposition theorems such as Lebesgue and Hewitt-Yosida decompositions--and control theorems such as Bartle-Dunford Schwartz and Rybakov theorems--for modular measures on L.

关键词： Pseudo-effect algebra pseudo-D-lattice D-uniformity lattice uniformity mod-ular measure

Fatigue strength of Al7075 notched plates based on the local SED averaged over a control volume

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Science China(Physics,Mechanics & Astronomy) 2014年第1期57卷 30-38页

作者： BERTO Filippo LAZZARIN paolo University of Padova Department of Management and Engineering Stradella San Nicola 3 36100 Vicenza Italy

When pointed V-notches weaken structural components, local stresses are singular and their intensities are expressed in terms of the notch stress intensity factors （NSIFs）. These parameters have been widely used for fatigue assessments of welded struc- tures under high cycle fatigue and sharp notches in plates made of brittle materials subjected to static loading. Fine meshes are required to capture the asymptotic stress distributions ahead of the notch tip and evaluate the relevant NSIFs. On the other hand, when the aim is to determine the local Strain Energy Density （SED） averaged in a control volume embracing the point of stress singularity, refined meshes are, not at all, necessary. The SED can be evaluated from nodal displacements and regular coarse meshes provide accurate values for the averaged local SED. In the present contribution, the link between the SED and the NSIFs is discussed by considering some typical welded joints and sharp V-notches. The procedure based on the SED has been also proofed to be useful for determining theoretical stress concentration factors of blunt notches and holes. In the second part of this work an application of the strain energy density to the fatigue assessment of A17075 notched plates is presented. The experimental data are taken from the recent literature and refer to notched specimens subjected to different shot peening treatments aimed to increase the notch fatigue strength with respect to the parent material.

关键词： strain energy density control volume coarse mesh

Real-world characteristics of hospitalized frail elderly patients with atrial fibrillation： can we improve the current prescription of anticoagulants？

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Journal of Geriatric Cardiology 2016年第3期13卷 226-232页

作者： Giorgio Annoni paolo Mazzola School of Medicine and Surgery University of Milano-Bicocca and Acute Geriatric Unit San Gerardo Hospital ASST Monza Monza Italy NeuroMI-Milan Center for Neuroscience Clinical Neurosciences Research Area Milano Italy

Background In elderly patients, especially those older than 80 years, atrial fibrillation （AF） is associated with an almost 25% in- creased risk of stroke. Stroke prophylaxis with anticoagulants is therefore highly recommended. The prevalence of factors that have been associated with a lower rate of prescription and adherence to anticoagulant therapy in these patients is little known. The objective of this study was to explore the clinical characteristics of elderly subjects, with and without AF, consecutively admitted to an acute geriatric unit, discussing factors that may decrease the persistence on stroke prophylaxis therapy. We also highlight possible strategies to overcome the barriers conditioning the current underuse of oral anticoagulants in this segment of the population. Methods A retrospective observational study was performed on a cohort of elderly patients with and without AF admitted to the Acute Geriatric Unit of San Gerardo Hospital （Monza, Italy）. Results Compared to patients without AF （n = 1216）, those with AF （n = 403） had a higher Charlson Comorbidity Index （3 vs. 2, P 〈 0.001）, number of administered drugs （4 vs. 3, P 〈 0.001）, rate of heart failure （36.5% vs. 12%, P 〈 0.001） and chronic kidney disease （20.6 vs. 13.2, P 〈 0.001）. Many patients with AF were frail （54%） or pre-frail （29%）. Conclusions Elderly patients with AF have higher rates of conditions that affect adherence to traditional anticoagulant therapy （vitamin K antagonists, VKA）. New direct oral anticoagulants （DOAs） can help overcome this problem. In order to prescribe the most appropriate VKA or DOAs, with the best efficacy/safety profile and the highest compliance, a comprehensive geriatric assessment should always accompany the scores for thrombotic and hemorrhagic risk stratification.

关键词： Anticoagulant prescription Atrial fibrillation Comorbidity Comprehensive geriatric assessment Frailty

A review of top-down cracking in asphalt pavements:Causes, models, experimental tools and future challenges

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Journal of Traffic and Transportation Engineering(English Edition) 2020年第5期7卷 541-572页

作者： Francesco Canestrari Lorenzo paolo Ingrassia Dipartimento di Ingegneria Civile Edile e Architettura(DICEA)Uniuersita Politecnica delle MarcheAncona 60131Italy

In the last decades,a new type of distress has been observed more and more frequently on asphalt *** distress,ascribable to fatigue failure,has been named top-down cracking(TDC) because it consists in longitudinal cracks that initiate on the pavement surface and then propagate downwards.A series of surveys recently carried out on Italian motorways highlighted that TDC can affect up to 20%-30% of the slow traffic ***,in order to achieve a better understanding of such distress,this paper reviews causes,models and experimental tools and highlights future challenges for *** literature review indicates that TDC can evolve on the pavement surface in three stages(i.e.,single crack,sister cracks,alligator cracking) and,below a certain depth,the cracks can form angles of 20°-40° with respect to the vertical *** though multiple factors contribute to TDC development,thick pavements are more likely to fail due to TDC induced by tire-pavement contact stresses,especially in the presence of open-graded friction courses(OGFCs).Moreover,in literature there are several TDC models based on mechanics(e.g.,fracture mechanics or continuum damage mechanics) which allow a rigorous study of crack initiation and *** challenges include the identification of a reliable and feasible test method,among those proposed in literature,to study the TDC performance of asphalt mixtures and the implementation of TDC in pavement management systems(PMSs) through the definition of criteria for TDC recognition in the field as well as for the rehabilitation depth ***,more research is needed for open-graded asphalt mixtures,which present critical drawbacks in terms of TDC.

关键词： Top-down cracking Flexible pavements Fatigue Cracking model Open-graded friction course Pavement management system

Non-isothermal Dissolution Modelling of Sigma Phase in Duplex Stainless Steels

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 859-868页

作者： paolo Ferro Alberto Fabrizi Franco Bonollo Department of Management and Engineering University of PadovaStradella San Nicola 336100 VicenzaItaly

In this work, the non-isothermal dissolution kinetics of the sigma phase in duplex stainless steels has been studied and modelled. A semi-empirical model is proposed to describe the kinetics of sigma phase precipitation/dissolution during continuous heating starting from the isothermal transformation kinetics. The proposed model, which presumes validity of the additivity rule, is validated by means of experimental investigations. A good agreement is found between experimental and analytical results.

关键词： Kinetics Non-isothermal dissolution Modelling Semi-empirical models Sigma phase Duplex stainless steels

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

Hydrodynamic finite-size scaling of the thermal conductivity in glasses

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npj Computational Materials 2023年第1期9卷 696-706页

作者： Alfredo Fiorentino paolo Pegolo Stefano Baroni SISSA—Scuola Internazionale Superiore di Studi Avanzati 34136 TriesteItaly CNR-IOM—Istituto Officina Materiali SISSA Unit34136 TriesteItaly

In the past few years,the theory of thermal transport in amorphous solids has been substantially extended beyond the Allen-Feldman *** resulting formulation,based on the Green-Kubo linear response or the Wigner-transport equation,bridges this model for glasses with the traditional Boltzmann kinetic approach for *** computational effort required by these methods usually scales as the cube of the number of atoms,thus severely limiting the size range of computationally affordable glass *** hydrodynamic arguments,we show how this issue can be overcome through a simple formula to extrapolate a reliable estimate of the bulk thermal conductivity of glasses from finite models of moderate *** showcase our findings for realistic models of paradigmatic glassy materials.

关键词： glasses conductivity thermal

Experimental evaluation of mechanical compression of lattice trusses made with Ti6Al4V for aerospace use

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Chinese Journal of Aeronautics 2024年第5期37卷 520-532页

作者： Carlo Giovanni FERRO Sara VARETTI paolo MAGGIORE Department of Mechanical and Aerospace Engineering Politecnico di TorinoCorso Duca degli AbruzziTorino 10124Italy

Lattice structures are three-dimensional structures composed of repeated geometrical shapes with multiple interconnected nodes,providing high strength-to-weight ratios,customizable properties,and efficient use of materials.A smart use of materials leads to reduced fuel consumption and lower operating costs,making them highly desirable for aircraft ***,the customizable properties of lattice structures allow for tailoring to specific design requirements,leading to improved performance and safety for *** advantages make lattice structures an important focus for research and development in the aviation *** paper presents an experimental evaluation of the mechanical compression properties of lattice trusses made with Ti6Al4V,designed for use in an anti-ice *** truss structures were manufactured using additive manufacturing techniques and tested under compressive loads to determine mechanical *** showed that lattice trusses exhibited high levels of compressive strength,making them suitable for use in applications where mechanical resistance and durability are critical,such as in anti-ice *** also highlight the potential of additive manufacturing techniques for the fabrication of lattice trusses with tailored mechanical *** study provides valuable insights into the mechanical behavior of Ti6Al4V lattice trusses and their potential applications in anti-ice systems,as well as other areas where high strength-to-weight ratios are *** results of this research contribute to the development of lightweight,efficient,and durable anti-ice systems for use in aviation and other industries.

关键词： Additive Manufacturing(AM) Selective Laser Sintering(SLM) Anti ice systems Lattice structures Aircraft on board systems Design of Experiments(DOE)