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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 manufacturers.Furthermore,the customizable properties of lattice structures allow for tailoring to specific design requirements,leading to improved performance and safety for aircraft.These advantages make lattice structures an important focus for research and development in the aviation industry.This paper presents an experimental evaluation of the mechanical compression properties of lattice trusses made with Ti6Al4V,designed for use in an anti-ice system.The truss structures were manufactured using additive manufacturing techniques and tested under compressive loads to determine mechanical properties.Results 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 systems.We also highlight the potential of additive manufacturing techniques for the fabrication of lattice trusses with tailored mechanical properties.The 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 required.The 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)

CBE Clima Tool:A free and open-source web application for climate analysis tailored to sustainable building design

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Building Simulation 2024年第3期17卷 493-508页

作者： giovanni Betti Federico Tartarini Christine Nguyen Stefano Schiavon Center for the Built Environment University of California BerkeleyBerkeleyUSA Berkeley Education Alliance for Research in Singapore SingaporeSingapore Heat and Health Research Incubator Faculty of Medicine and HealthThe University of SydneyCamperdownAustralia College of Letters and Sciences University of California BerkeleyBerkeleyUSA

Climate-responsive building design holds immense potential for enhancing comfort,energy efficiency,and environmental sustainability.However,many social,cultural,and economic obstacles might prevent the wide adoption of designing climate-adapted buildings.One of these obstacles can be removed by enabling practitioners to easily access,visualize and analyze local climate data.The CBE Clima Tool(Clima)is a free and open-source web application that offers easy access to publicly available weather files and has been created for building energy simulation and design.It provides a series of interactive visualizations of the variables contained in the EnergyPlus Weather Files and several derived ones like the UTCI or the adaptive comfort indices.It is aimed at students,educators,and practitioners in the architecture and engineering fields.Since its inception,Clima’s user base has exhibited robust growth,attracting over 25,000 unique users annually from across 70 countries.Our tool is poised to revolutionize climate-adaptive building design,transcending geographical boundaries and fostering innovation in the architecture and engineering fields.

关键词： architectural design climate analysis sustainable building design web application building energy simulation open-source software

Polymerization of 1,3-Butadiene with Catalysts Based on Cobalt Dichloride Complexes with Aminophosphines: Switching the Regioselectivity by Varying the MAO/Co Molar Ratio

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Chinese Journal of Polymer Science 2024年第4期42卷 501-510页

作者： giovanni Ricci Anna Sommazzi Francesco Masi Alessandra Forni CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via A.Corti 1220133MilanoItaly Viale giovanni XXIII 34 I-28100NovaraNOItaly Via Galvani 7 I-26866Sant’Angelo LodigianoLOItaly CNR-Istituto di Scienze e Tecnologie Molecolari“Giulio Natta”(SCITEC) via C.Golgi 1920133MilanoItaly

Several novel cobalt dichloride complexes with amino-phosphine bidentate ligands were synthesized and characterized.For some of them single crystals were obtained and their molecular structure was determined by X-ray diffraction method.All the complexes were then used in combination with MAO for the polymerization of 1,3-butadiene,obtaining polymers with different structures(i.e.,predominantly 1,2 or cis-1,4)mainly depending on the type of ligand and on the MAO/Co molar ratio.The behavior of these novel catalysts was compared with that exhibited,in the polymerization of the same monomer,by the systems CoCl_(2)(PR3)2-MAO and CoCl_(2)(PRPh2)2-MAO(R=alkyl or cycloalkyl group),and by the systems based on cobalt dichloride complexes with various bi-and tridentate ligands(e.g.,diphosphines,bis-imines,pyridyl-imines,bis-iminopyridines).The comparison between the different systems allowed us to make some clarity about the actual and effective role played by the various types of ligands in the polymerization of conjugated dienes with catalytic systems CoCl_(2)(L)-MAO,in which L=mono-,bi-,or tri-dentate ligand.

关键词： 1,3-Butadiene Stereospecific polymerization Cobalt catalysts Regioselectivity Aminophosphine ligands Crystal structures Chelate rings

A novel approach to the dynamic response analysis of Euler-Bernoulli beams resting on a Winkler soil model and subjected to impact loads

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 389-401页

作者： Adolfo Foriero Filippo Santucci de Magistris giovanni Fabbrocino Département de génie civil et de génie des eaux Pavillon Adrien-PouliotUniversitéLavalQuébecCanada Dipartimento di Bioscienze e Territorio Universitàdegli Studi del MoliseCampobassoItaly Construction Technologies Institute National Research CouncilITC-CNRL’AquilaItaly

This work presents a novel approach to the dynamic response analysis of a Euler-Bernoulli beam resting on a Winkler soil model and subjected to an impact loading.The approach considers that damping has much less importance in controlling the maximum response to impulsive loadings because the maximum response is reached in a very short time,before the damping forces can dissipate a significant portion of the energy input into the system.The development of two sine series solutions,relating to different types of impulsive loadings,one involving a single concentrated force and the other a distributed line load,are presented.This study revealed that when a simply supported Euler-Bernoulli beam,resting on a Winkler soil model,is subject to an impact load,the resulting vertical displacements,bending moments and shear forces produced along the span of the beam are considerably affected.In particular,the quantification of this effect is best observed,relative to the corresponding static solution,via an amplification factor.The computed impact amplification factors,for the sub-grade moduli used in this study,were in magnitude greater than 2,thus confirming the multiple-degree-of-freedom nature of the problem.

关键词： beam-Winkler-soil model sub-grade moduli impact load impact distributed line load dynamic solution impact amplification factor

On the optimisation of age of the air in the breathing zone of floor heating systems:The role of ventilation design

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Energy and Built Environment

Energy and Built Environment 2024年第1期5卷 130-142页

作者： Aminhossein Jahanbin giovanni Semprini Department of Industrial Engineering(DIN) Alma Mater Studiorum-University of BolognaViale Risorgimento 240136 BolognaItaly CIRI-Centro Interdipartimentale di Ricerca Industriale Edilizia e Costruzioni Alma Mater Studiorum-University of BolognaVia del Lazzaretto 15/540131 BolognaItaly

For a mechanically ventilated space,the nominal age of the air can be obtained by the reciprocal of the air change rate.However,values of the local mean age of the air in practice may differ to some extent from the nominal one since the nominal time constant employs as reference the theoretical optimum model.This discrepancy could become more prominent in spaces conditioning with both ventilation and heating system where the indoor air pattern is affected by turbulent mixed convection flow.Given importance of knowledge on the distribution of age of the air in these spaces,the present study provides insights on how ventilation design in floor heating systems can optimise the delivery of fresh air into the breathing zone.In this context,by establishing a computational fluid dynamic(CFD)model validated against experimental data,the local mean age of the air as well as the indoor air quality(IAQ)indices in the breathing zone of the floor heating system are examined under different ventilation modes.Six different ventilation scenarios are regarded in order to find the optimal ventilation design in terms of the delivery of the fresh air and ventilation effectiveness in occupied space.Furthermore,the integrated effects of the floor temperature and inlet supply temperature along with the ventilation design on the distribution of local age of the air are addressed.The obtained results indicate that the up-supply ventilation strategy is more efficient than down-supply one in the ventilation effectiveness and delivery of fresh air into the breathing zone.Moreover,it is shown that the mean age of the air in the breathing zone of the up-supply ventilation increases with increment of the Ri(Richardson number),whereas an increase in Ri improves the delivery of fresh air in down-supply mode.For a given floor temperature,the similar trend is also observed in the variation of age of the air with the characteristic temperature of supply inlet,namely the temperature difference between inlet supply and surrounding walls.

关键词： Age of the air Indoor air quality Ventilation Floor heating CFD

The potential for an old-growth forest to store carbon in the topsoil:A case study at Sasso Fratino,Italy

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Journal of Forestry Research 2024年第2期35卷 23-32页

作者： Tommaso Chiti Nicola Benilli giovanni Mastrolonardo Giacomo Certini Dipartimento per la Innovazione nei Sistemi Biologici Agroalimentari e Forestali(DIBAF)Universitàdella TusciaVia San C.de Lellis Snc01100 ViterboItaly Dipartimento di Scienze e Tecnologie Agrarie AlimentariAmbientali e Forestali(DAGRI)Universitàdegli Studi di FirenzeP.le delle Cascine 1850144 FirenzeItaly

There is considerable interest devoted to oldgrowth forests and their capacity to store carbon(C)in biomass and soil.Inventories of C stocks in old-growth forests are carried out worldwide,although there is a lack of information on their actual potential for C sequestration.To further understand this,soil organic carbon(SOC)was measured in one of Italy's best-preserved old-growth forests,the Sasso Fratino Integral Nature Reserve.This reserve is on the World Heritage List along with other ancient beech forests of Europe,and it is virtually untouched due to the steepness of the terrain,even before legal constraints were imposed.Although the sandstone-derived soils are often shallow,they are rich in organic matter.However,no quantification had been carried out.By systematically sampling the topsoil across the forest,we accurately determined the average amount of SOC(62.0±16.9 Mg ha^(–1))and nitrogen(4.0±1.2 Mg ha^(–1))in the top 20 cm.Using the CENTURY model,future dynamics of SOC stocks were predicted to 2050 according to two climate scenarios,A1F1 and B2,the first of high concern and the second more optimistic.The model projected an increase of 0.2 and 0.3 Mg ha^(–1)a^(–1)by 2030 under the A1F1 and B2 scenarios,respectively,suggesting that the topsoil in old-growth forests does not reach equilibrium but continues accumulating SOC.However,from 2030 to 2050,a decline in SOC accumulation is predicted,indicating SOC net loss at high altitudes under the worst-case scenario.This study confirms that soils in oldgrowth forests play a significant role in carbon sequestration.It also suggests that climate change may affect the potential of these forests to store SOC not only in the long term but also in the coming years.

关键词： Carbon sequestration CENTURY model Climate change Forest soil Soil nitrogen

Non-invasive prenatal testing can detect silent cancers in expecting mothers

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Genes & Diseases 2024年第2期11卷 585-588页

作者： Alessandro Ottaiano Monica Ianniello Nadia Petrillo Mariachiara Santorsola Luigia De Falco Salvatore giovanni Castaldi Maria Antonietta Castaldi Valentina Giudice Carmine Selleri giovanni Savarese Unit of Innovative Therapies for Abdominal Metastases Istituto Nazionale Tumori di NapoliIRCCS “G.Pascale”Via Mariano SemmolaNapoli 80131Italy AMES Centro Polidiagnostico Strumentale SRLVia Padre Carmine Fico 24Casalnuovo Di Napoli 80013Italy Specialization School of Clinical Pathology Università degli Studi di SalernoVia Giovanni Paolo II 132Fisciano 84084Italy Unit of High-Risk Pregnancy and Prenatal Diagnosis University Hospital “San Giovanni di Dio e Ruggi d'Aragona”Via San LeonardoSalerno 84125Italy Hematology and Transplant Center University Hospital “San Giovanni di Dio e Ruggi d'Aragona”Via San LeonardoSalerno 84125Italy Department of Medicine Surgery and Dentistry“Scuola Medica Salernitana”Via Salvador Allende 43Baronissi 84081Italy

Pregnancy is a unique physiological state in which several changes occur.One of the most important aspects is the maternal immune system,which sets to tolerate the presence of thedeveloping fetus(a semi-allogeneic organism),while at the same time providing protection against pathogens.1 Pregnancy has long been known to affect the risk of certain cancers including breast cancer in the short term,gestational trophoblastic disease(GTD),cervical cancer,and melanoma.2,3 The reasons for the increased risk of these cancers during pregnancy are not fully understood,but several hypotheses have been proposed as the hormonal and immune system changes.

关键词： mother cancers fetus

Lunar orbits for telecommunication and navigation services

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Astrodynamics 2024年第1期8卷 209-220页

作者： Marco Cinelli Emiliano Ortore giovanni Mengali Alessandro A.Quarta Christian Circi Istituto di Astrofisica e Planetologia Spaziali(IAPS) Istituto Nazionale di Astrofisica(INAF)Via del Fosso del Cavaliere 100Roma00133Italy School of Aerospace Engineering Sapienza University of RomeVia Salaria 881Rome00138Italy Department of Civil and Industrial Engineering University of PisaPisa56122Italy Department of Astronautical Electricaland Energy EngineeringSapienza University of RomeVia Salaria 851Rome00138Italy

Orbits that are frozen in an averaged model,including the effect of a disturbing body laying on the equatorial plane of the primary body and the influence of the oblateness of the primary body,have been applied to probes orbiting the Moon.In this scenario,the main disturbing body is represented by the Earth,which is characterized by a certain obliquity with respect to the equatorial plane of the Moon.As a consequence of this,and of the perturbing effects that are not included in the averaged model,such solutions are not perfectly frozen.However,the orbit eccentricity,inclination,and argument of pericenter present limited variations and can be set to guarantee the fulfillment of requirements useful for lunar telecommunication missions and navigation services.Taking advantage of this,a practical case of a Moon-based mission was investigated to propose useful solutions for potential near-future applications.

关键词： lunar orbits frozen orbits lunar telecommunications lunarnavigation services

A novel 2D-GO@WS2 electrochemical platform for the determination of thiram fungicide

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Journal of Environmental Sciences 2024年第2期136卷 226-236页

作者： Khouloud Abid Daniela Iannazzo Consuelo Celesti Amani Khaskhoussi Antonino Foti Ramzi Maalej Pietro Giuseppe Gucciardi giovanni Neri Department of Engineering University of MessinaC.da Di DioI-98166 MessinaItaly INSTM Research Unity of MessinaItaly Laboratory of Dielectric and Photonic Materials Faculty of Sciences of SfaxSfaxUniversitySfax 3018Tunisia CNR IPCF Istituto per i Processi Chimico-Fisici viale F.Stagno D’Alcontres 37I-98156 MessinaItaly

In this paper,the determination of Thiram fungicide by a novel modified screen-printed carbon electrode(SPCE)fabricated modifying the working electrode(WE)with 2D-GO/WS2nanohybrid composites,is reported.Scanning electron microscopy(SEM),Raman spectroscopy,and fluorescence analysis(PL)were used to reveal the morphological and microstructural characteristics of the 2D-GO/WS2 nanohybrids with different graphene oxide:tungsten disulphide(GO:WS_(2))ratio.Electrochemical characterization demonstrated that the 2D-WS2/GO nanohybrids having a GO:WS_(2)ratio=2:1 shows the highest electrocatalytic activity towards oxidation of Thiram.The developed sensor permits the quantification of Thiram in the linear range 0.083-0.33μM with a limit of detection(LOD)of 0.02μM,which is below the legal limits for this fungicide in drinking water or foods.

关键词： WS_(2)nanosheets Graphene Oxide(GO) Electrochemical sensor Fungicides Thiram