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Laser-optimized Pt-Y alloy nanoparticles embedded in Pt-Y oxide matrix for high stability and ORR electrocatalytic activity

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Journal of Energy Chemistry 2024年第5期92卷 508-520页

作者： Riccardo Brandiele andrea Guadagnini Mattia Parnigotto Federico Pini Vito Coviello Denis Badocco Paolo Pastore Gian andrea Rizzi andrea Vittadini Daniel Forrer Vincenzo Amendola Christian Durante Department of Chemical Sciences University of PaduaVia Marzolo 135131 PadovaItaly Istituto di Chimica della Materia Condensata e di Tecnologie per l’Energia ICMATE-CNR via Marzolo 1 I-35131 PadovaItaly

The development of active yet stable catalysts for oxygen reduction reaction(ORR)is still a major issue for the extensive permeation of fuel cells into everyday *** nanostructured Pt catalysts are to date the best available systems in terms of activity,the same is not true for stability,particularly under operating *** this work,Pt_(Х)Y alloy nanoparticles are proposed as active and durable electrocatalysts for ***_(Х)Y nanoalloys are synthesized and further optimized by laser ablation in liquid followed by laser fragmentation in *** novel integrated laser-assisted methodology succeeded in producing Pt_(Х)Y nanoparticles with the ideal size(1000 A g^(-1).At the same time,the nanoalloys are embedded in a fine Pt oxide matrix,which allows a greater stability of the catalyst than the commercial Pt reference,as directly verified on a gas diffusion electrode.

关键词： Electrocatalysis GDE ORR Pt_(2)Y Pt_(3)Y LAL LFL Oxide support Pto Nanoalloys

Pettifor maps of complex ternary two-dimensional transition metal sulfides

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npj Computational Materials 2022年第1期8卷 1692-1702页

作者： andrea Silva Jiangming Cao Tomas Polcar Denis Kramer Faculty of Engineering and Physical Sciences University of SouthamptonUniversity RoadSO171BJSouthamptonUK National Centre for Advanced Tribology Study University of SouthamptonSouthamptonUK Faculty of Mechanical and Civil Engineering Helmut-Schmidt-Universität/Universität der Bundeswehr HamburgHolstenhofweg 8522043HamburgGermany Advanced Materials Group Department of Control EngineeringFaculty of Electrical EngineeringCzech Technical University in Prague(CTU)PragueCzech Republic Department of Heterogeneous Catalysis Helmholtz-Zentrum HereonMax-Planck-Strasse 1GeesthachtGermany

Alloying is an established strategy to tune the properties of bulk compounds for desired *** the advent of nanotechnology,the same strategy can be applied to 2D materials for technological applications,like single-layer transistors and solid *** we present a systematic analysis of the phase behaviour of substitutional 2D alloys in the Transition Metal Disulfides(TMD)*** phase behaviour is quantified in terms of a metastability metric and benchmarked against many-body expansion of the energy *** show how the metastability metric can be directly used as starting point for setting up rational search strategies in phase space,thus allowing for targeted further computational prediction and analysis of *** results presented here also constitute a useful guideline for synthesis of TMDs binary alloys via a range of synthesis techniques.

关键词： alloys sulfide behaviour

Dynamical Criticality:Overview and Open Questions

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Journal of Systems Science & Complexity 2018年第3期31卷 647-663页

作者： ROLI andrea VILLANI Marco FILISETTI Alessandro SERRA Roberto Department of Computer Science and Engineering (DISI) Campus of Cesena University of Bologna Italy Department of Physics Informatics and Mathematics University of Modena and Reggio Emilia Italy European Centre for Living Technology Venezia Italy Explora s.r.l. Roma Italy & European Centre for Living Technology Venezia Italy

Systems that exhibit complex behaviours are often found in a particular dynamical con- dition, poised between order and disorder. This observation is at the core of the so-called criticality hypothesis, which states that systems in a dynamical regime between order and disorder attain the highest level of computational capabilities and achieve an optimal trade-off between robustness and flexibility. Recent results in cellular and evolutionary biology, ueuroscience and computer science have revitalised the interest in the criticality hypothesis, emphasising its role as a viable candidate general law in adaptive complex systems. This paper provides an overview of the works on dynamical criticality that are -- To the best of our knowledge -- Particularly relevant for the criticality hypothesis. The authors review the main contributions concerning dynamics and information processing at the edge of chaos, and illustrate the main achievements in the study of critical dynamics in biological systems. Finally, the authors discuss open questions and propose an agenda for future work.

关键词： Attractors criticality dynamical regimes edge of chaos phase transitions.

Visual communication in social play of a hierarchical carnivore species:the case of wild spotted hyenas

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Current Zoology 2022年第4期68卷 411-421页

作者： andrea Paolo Nolfo Grazia Casetta Elisabetta Palagi Department of Biology Unit of EthologyUniversity of PisaVia A.Volta 6Pisa56126Italy Natural History Museum University of PisaVia Roma 79CalciPisa56011Italy

Communication relies on signals that can be produced via different sensory modalities to modify receivers’*** social interactions,the possibility to perceive subtle visual cues enhances the use of facial expressions to exchange *** of the most appropriate fields to explore the specific design features of visual signals is play ***,we explored the production and potential role of Relaxed Open Mouth(ROM)and Head Bobbing(HB)in regulating play fighting of wild spotted hyenas Crocuta crocuta,a highly hierarchical carnivore *** accordance with the assumptions of the signal optimization theory,wild hyenas produced ROM and HB almost exclusively when the sender was in direct visual contact with the receiver thus suggesting that senders were attentive to the playmates’*** to HB,the sequential analysis revealed that ROM often anticipated offensive patterns such as play biting thus supporting the hypothesis that ROM,but not HB,is a metacomunicative ***,when the offensive patterns were biased toward one of the 2 players,the session was punctuated by a higher number of *** findings support the general hypothesis that these 2 visual signals can play different roles in the management of play fighting in this carnivore *** complementary use of ROM and HB would suggest that spotted hyenas are highly competent and fast in processing facial displays of different nature to correctly“read others’intentions”and respond with appropriate motor actions to avoid misunderstanding during one of the most multifaceted and risky social interaction.

关键词： Crocuta crocuta head and facial signals head bobbing metacommunication play fighting relaxed open mouth display

Julolidine-labelled fluorinated block copolymers for the development of two-layer films with highly sensitive vapochromic response

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Science China Chemistry 2018年第8期61卷 947-956页

作者： Camillo Sorgi Elisa Martinelli Giancarlo Galli andrea Pucci Department of Chemistry and Industrial Chemistry University of Pisa 56124 Pisa Italy National Interuniversity Consortium of Materials Science and Technology UdR Pisa 56124 Pisa Italy

Fluorinated block copolymers composed of a polystyrene(Sx) first block and a polyacrylate second block carrying hydrophobic/lipophobic perfluorohexyl side chains(AF) were prepared by atom transfer radical polymerization(ATRP). Fluorescence emission properties were imparted to the copolymers by incorporation in the second block of a julolidine-based fluorescent molecular rotor(JCBF). The synthesized block copolymers were used as the fluorescent low-surface energy thin top-layer onto a polystyrene bottom-layer to produce novel two-layer film vapochromic sensors. Contact angle and X-ray photoelectron spectroscopy(XPS) measurements revealed that the two-layer film surfaces were hydrophobic and lipophobic at the same time and highly enriched in fluorine content as a result of the effective segregation of the perfluorinated tails to the polymer-air *** fluorescence intensity of the two-layer films decreased significantly when they were exposed to vapours of organic solvents,including tetrahydrofurane, chloroform, and trifluorotoluene. However, an AF content-dependent sensing behaviour was also observed, with the two-layer films containing the copolymer with the shorter fluorinated block giving a more rapid and almost quantitative decrease in fluorescence variation. Fluorescence emission of the films was also proved to vary with *** the vapochromic and thermochromic responses were reversible after successive solicitation cycles. The fluorescence variation of the two-layer films was much more marked than that of the corresponding PS/JCBF blend, thus providing a system potentially applicable as highly sensitive volatile organic compound(VOC) sensor, thanks to the active role of the fluorinated block in promoting the migration of the fluorophore to the outermost surface layers.

关键词： fluorinated block copolymers fluorescent molecular rotors vapochromism

Sliding wear behavior of fully nanotwinned Cu alloys

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Friction 2019年第3期7卷 260-267页

作者： Jianfeng YAN Andrew LINDO Ruth SCHWAIGER andrea MHODGE Department of Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA90089USA Department of Mechanical Engineering Tsinghua UniversityBeijing100084China Institute for Applied Materials Karlsruhe Institute of Technology(KIT)Eggenstein-Leopoldshafen76344Germany

Highly nanotwinned(NT) metals have advantages such as high strength,good ductility,favorable corrosion resistance,and thermal *** has been demonstrated that the introduction of high density NT microstructures can enhance the tribological properties of ***,the influence of the microstructure and the composition of NT alloys on the tribological behavior are not *** this work,the sliding wear behavior of fully NT materials,specifically Cu-Al and Cu-Ni alloys,are studied by a nanoscratch technique using a *** effects of microstructure and chemical composition on the wear properties are also *** results show that the chemical composition has an obvious influence on the wear resistance and microstructural *** NT Cu-Al alloys,the hardness and sliding wear resistance improve with increased Al content from Cu-2 wt.%Al to Cu-6 wt.%*** Cu-10 wt.%Ni alloy shows even better wear resistance than Cu-6 wt.%*** microstructural analysis shows that NT Cu alloys with higher wear resistance correspond to a smaller deformation-affected *** improvement of sliding wear properties of Cu-Al alloys with higher Al content may be ascribed to their decreased stacking fault *** Cu-Ni alloy shows better wear resistance than Cu-Al alloy,this may be related to the formation of intermetallic compounds in Cu-Al *** study broadens the knowledge about tribological properties of NT materials and provides a potential method to optimize their sliding wear resistance by altering the chemical composition of NT Cu alloys.

关键词： nanotwinned alloys thin film stacking fault energy tribology

Role and timing of endoscopy in acute biliary pancreatitis

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World Journal of Gastroenterology 2015年第40期21卷 11205-11208页

作者： andrea Anderloni Alessandro Repici Department of Gastroenterology Digestive Endoscopy UnitHumanitas Research Hospital

The role and timing of endoscopy in the setting of acute biliary pancreatitis(ABP) is still being debated. Despite numerous randomized trials have been published,there is an obvious lack of consensus on the indications and timing of endoscopic retrograde cholangiopancreatography(ERCP) in ABP in metaanalyses and nationwide guidelines. The present editorial has been written to clarify the role of endoscopy in ABP. In clinical practice the decision to perform an ERCP is often based on biochemical and radiological criteria despite they already have been shown to be unreliable predictors of common bile duct stone presence. Endoscopic ultrasonography(EUS) is not currently a worldwide standard diagnostic procedure early in the course of acute biliary pancreatitis,but it has been shown to be accurate,safe and cost effective in diagnosing biliary obstructions compared with magnetic resonance cholangiopancreatography and ERCP and therefore in preventing unnecessary ERCP and its related complications. Early EUS in ABP allows,if appropriate,immediate endoscopic treatment and significant spare of unnecessary operative procedures thus reducing possible related complications.

关键词： Acute biliary pancreatitis Choledocolithiasis Comm

Interactional behaviors of the parasitic beetle Paussus favieri with its ant host Pheidole pallidula:the mimetic role of the acoustical signals

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Insect Science 2021年第2期28卷 548-554页

作者： Simone Fattorini Emanuela Maurizi andrea Di Giulio Department of Life Health and Environmental SciencesUniversity of L'AquilaL'AquilaItaly Research Centre for Plant Protection and Certification Council for Agricultural Research and Economics(CREA-DC)FlorenceItaly Department of Science LIMERoma Tre UniversityRomeItaly

The social parasitic beetle Puussus favieri(Coleoptera,Carabidae,Paussini)performs different types of stridulations,which sclectively mimic those emitted by dif-ferent ant castes of its host Pheidole pallidula(Hymenoptera,Formicidae,Myrmicinae).However,the significance of this acoustical mimicry for the success of the parasitic strat-egy and the behaviors elicited in the host ants by stridulations was *** reared Paussus favieri in Pheidole pallidula colonies and filmed their interacting *** analyzed in slow motion the behavior of ants near a stridulating *** analyzed sep-arately trains of pulse(Pa+Pb,produced by repeated rubbings)and single pulse(Pc,produced by a single rubbing)of stridulations,clearly recognizable from the shaking up and down of the beetle hind *** associated them with differcent ant *** full repertoire of sounds produced by P:favieri elicited benevolent responses both in workers and *** found that different signals elicit different(sometimes multiplc)bchaviors in ants,with different frequency in the two ant ***,Pc(alone or in conjunction with other types of pulses)appears to be the type of acoustic signal mostly responsible for all recorded *** results indicate that the acoustic channel plays a pivotal role in the host-parasite *** that a parasite uses the acoustical channel so intensively,and in such a complicated way to trigger ant bchaviors,indicates that acoustic signals may be more important in ant societies than commonly recognized.

关键词： acoustical channel ant castes beetle-ant interactions behavioral repertoire social parasites stridulation

Synthetic PMU Data Creation Based on Generative Adversarial Network Under Time-varying Load Conditions

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Journal of Modern Power Systems and Clean Energy 2023年第1期11卷 234-242页

作者： Xiangtian Zheng andrea Pinceti Lalitha Sankar Le Xie Department of Electrical and Computer Engineering Texas A&M UniversityCollege StationTX 77840USA Dominion Energy RichmondVA 23219USA School of Electrical Computerand Energy EngineeringArizona State UniversityTempeAZ 85281USA IEEE

In this study,a machine learning based method is proposed for creating synthetic eventful phasor measurement unit(PMU)data under time-varying load *** proposed method leverages generative adversarial networks to create quasi-steady states for the power system under slowly-varying load conditions and incorporates a framework of neural ordinary differential equations(ODEs)to capture the transient behaviors of the system during voltage oscillation events.A numerical example of a large power grid suggests that this method can create realistic synthetic eventful PMU voltage measurements based on the associated real PMU data without any knowledge of the underlying nonlinear dynamic *** results demonstrate that the synthetic voltage measurements have the key characteristics of real system behavior on distinct time scales.

关键词： TermsPhasor measurement unit(PMU) generative adversarial networks neural ordinary differential equations data-driven method