检索结果-南通市图书馆

Experimental evaluation of mechanical compression of lattice trusses made with Ti6Al4v for aerospace use

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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)

Metal-Halide Perovskite Submicrometer-Thick Films for Ultra-Stable Self-Powered Direct X-Ray Detectors

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2024年第9期16卷 410-431页

作者： Marco Girolami Fabio Matteocci Sara Pettinato valerio Serpente Eleonora Bolli Barbara Paci Amanda Generosi Stefano Salvatori Aldo Di carlo Daniele M.Trucchi CNR‑ISM Consiglio Nazionale delle RicercheIstituto di Struttura della MateriaSede Secondaria di MontelibrettiDiaTHEMA LabStrada Provinciale 35D900010 MontelibrettiRomeItaly CHOSE–Centre for Hybrid and Organic Solar Energy Department of Electronic EngineeringUniversity of Rome“Tor Vergata”Via del Politecnico 100133 RomeItaly Faculty of Engineering Universita degli Studi Niccolo CusanoVia don Carlo Gnocchi 300166 RomeItaly SpecXLab CNR‑ISMConsiglio Nazionale Delle RicercheIstituto di Struttura Della MateriaArea della Ricerca di Tor VergataVia del Fosso del Cavaliere 10000133 RomeItaly

Metal-halide perovskites are revolutionizing the world of X-ray detectors,due to the development of sensitive,fast,and cost-effective ***-powered operation,ensuring portability and low power consumption,has also been recently demonstrated in both bulk materials and thin ***,the signal stability and repeatability under continuous X-ray exposure has only been tested up to a few hours,often reporting degradation of the detection *** it is shown that self-powered direct X-ray detectors,fabricated starting from a FAPbBr_(3)submicrometer-thick film deposition onto a mesoporous TiO_(2)scaffold,can withstand a 26-day uninterrupted X-ray exposure with negligible signal loss,demonstrating ultra-high operational stability and excellent *** structural modification is observed after irradiation with a total ionizing dose of almost 200 Gy,revealing an unexpectedly high radiation hardness for a metal-halide perovskite thin *** addition,trap-assisted photoconductive gain enabled the device to achieve a record bulk sensitivity of 7.28 C Gy^(−1)cm^(−3)at 0 v,an unprecedented value in the field of thin-film-based photoconductors and photodiodes for“hard”***,prototypal validation under the X-ray beam produced by a medical linear accelerator for cancer treatment is also introduced.

关键词： Metal-halide perovskite thin films Direct X-ray detectors Self-powered devices Operational stability Medical linear accelerator

The outcomes and safety of patients undergoing endoscopic retrograde cholangiopancreatography combining a single-use cholangioscope and a single-use duodenoscope:A multicenter retrospective international study

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 71-76页

作者： Alessandro Fugazza Matteo Colombo Michel Kahaleh v.Raman Muthusamy Bick Benjamin Wim Laleman Carmelo Barbera carlo Fabbri Jose Nieto Abed Al-Lehibi Mohan Ramchandani Amy Tyberg Haroon Shahid Avik Sarkar Dean Ehrlich Stuart Shermand Cecilia Binda Marco Spadaccini Andrea Iannone Kareem Khalaf Nageshwar Reddy Andrea Anderloni Alessandro Repici Division of Gastroenterology and Digestive Endoscopy Humanitas Research Hospital-IRCCSVia Manzoni 5620089RozzanoMilanoItaly Gastroenterology Rutgers Robert Wood JohnsonNew BrunswickNew JerseyUSA vatche and Tamar Manoukian Division of Digestive Diseases University of CaliforniaLos Angeles School of Medicine at UCLALos AngelesCaliforniaUSA Division of Digestive and Liver Disorders Indiana University School of MedicineIndianapolisINUSA Department of Gastroenterology and Hepatology University Hospitals LeuvenKU Leuven3000 LeuvenBelgium U.O.C.di Gastroenterologia ed Endoscopia Digestiva Ospedale Giuseppe MazziniASL TeramoItaly Gastroenterology and Digestive Endoscopy Unit Forlì-Cesena HospitalsAUSL RomagnaForlì-CesenaItaly Borland Groover Clinic JacksonvilleFloridaUSA Department of Gastroenterology and Hepatology King Fahad Medical CityRiyadhSaudi Arabia Asian Institute of Gastroenterology HyderabadIndia Section of Gastroenterology Department of Emergency and Organ TransplantationUniversity of BariBari 70124Italy Department of Biomedical Sciences Humanitas UniversityVia Rita Levi Montalcini 420090Pieve EmanueleMilanItaly

Background: Duodenoscope-related multidrug-resistant organism(MDRO) infections raise concerns. Disposable duodenoscopes have been recently introduced in the market and approved by regulatory agencies with the aim to reduce the risk of endoscopic retrograde cholangiopancreatography(ERCP) associated infections. The aim of this study was to evaluate the outcome of procedures performed with single-use duodenoscopes in patients with clinical indications to single-operator cholangiopancreatoscopy. Methods: This is a multicenter international, retrospective study combining all patients who underwent complex biliopancreatic interventions using the combination of a single-use duodenoscope and a single-use cholangioscope. The primary outcome was technical success defined as ERCP completion for the intended clinical indication. Secondary outcomes were procedural duration, rate of cross-over to reusable duodenoscope, operator-reported satisfaction score(1 to 10) on performance rating of the single-use duodenoscope, and adverse event(AE) rate. Results: A total of 66 patients(26, 39.4% female) were included in the study. ERCP was categorized according to ASGE ERCP grading system as 47(71.2%) grade 3 and 19(28.8%) grade 4. The technical success rate was 98.5%(65/66). Procedural duration was 64(interquartile range 15-189) min, cross-over rate to reusable duodenoscope was 1/66(1.5%). The satisfaction score of the single-use duodenoscope classified by the operators was 8.6 ± 1.3 points. Four patients(6.1%) experienced AEs not directly related to the single-use duodenoscope, namely 2 post-ERCP pancreatitis(PEP), 1 cholangitis and 1 ***: Single-use duodenoscope is effective, reliable and safe even in technically challenging procedures with a non-inferiority to reusable duodenoscope, making these devices a viable alternative to standard reusable equipment.

关键词： Single-operator cholangioscopy Single-use duodenoscope Endoscopic retrograde cholangiopancreatography Indeterminate biliary stricture Difficult biliary stones

SANC Monte carlo programs for small-angle Bhabha scattering

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov S.G.Bondarenko I.R.Boyko L.v.Kalinovskaya A.A.Kampf R.R.Sadykov v.L.Yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna State University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using SANC Monte carlo event generator ReneSANCe and integrator MCSANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 Gev for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte carlo simulation

Anomalies in the short-range local environment and atomic diffusion in single crystalline equiatomic CrMnFeCoNi highentropy alloy

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第6期17卷 5336-5348页

作者： Alevtina Smekhova Daniel Gaertner Alexei Kuzmin Ana Guilherme Buzanich Goetz Schuck Ivo Zizak Gerhard Wilde Kirill v.Yusenko Sergiy Divinski Helmholtz-Zentrum Berlin für Materialien und Energie(HZB) D-12489 BerlinGermany Institute of Materials Physics University of MünsterD-48149 MünsterGermany Institute of Solid State Physics University of LatviaLV-1063 RigaLatvia Bundesanstalt für Materialforschung und–prüfung(BAM) D-12489 BerlinGermany

Multi-edge extended X-ray absorption fine structure(EXAFS)spectroscopy combined with reverse Monte carlo(RMC)simulations was used to probe the details of element-specific local coordinations and component-dependent structure relaxations in single crystalline equiatomic CrMnFeCoNi high-entropy alloy as a function of the annealing *** representative states,namely a high-temperature state,created by annealing at 1373 K,and a low-temperature state,produced by long-term annealing at 993 K,were compared in *** features identified in atomic configurations of particular principal components indicate variations in the local environment distortions connected to different degrees of compositional disorder at the chosen representative *** detected changes provide new atomistic insights and correlate with the existence of kinks previously observed in the Arrhenius dependencies of component diffusion rates in the CrMnFeCoNi high-entropy alloy.

关键词： high-entropy alloys diffusion short-range order extended X-ray absorption fine structure(EXAFS) reverse Monte carlo

Biomimetics of Campaniform Sensilla:Measuring Strain from the Deformation of Holes

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2007年第2期4卷 63-76页

作者： Julian F. v. vincent Sally E. Clift carlo Menon Department of Mechanical Engineering The University of BathBath BA2 7AYUK Advanced Concepts Team European Space Agency2201 AZ NoordwijkThe Netherlands

We present a bio-inspired strategy for designing embedded strain sensors in space structures. In insects, the campaniform sensillum is a hole extending through the cuticle arranged such that its shape changes in response to loads. The shape change is rotated through 90° by the suspension of a bell-shaped cap whose deflection is detected by a cell beneath the cuticle. It can be sensitive to displacements of the order of 1 nm. The essential morphology, a hole formed in a plate of fibrous composite mate- rial, was modelled by Skordos et al. who showed that global deformation of the plate （which can be flat, curved or a tube） induces higher local deformation of the hole due to its locally higher compliance. Further developments reported here show that this approach can be applied to groups of holes relative to their orientation. , The morphology of the sensillum in insects suggests that greater sensitivity can be achieved by arranging several holes in a regular pattern; that if the hole is oval it can be ＂aimed＂ to sense specific strain directions; and that either by controlling the shape of the hole or its relationship with other holes it can have a tuned response to dynamic strains. We investigate space applications in which novel bio-inspired strain sensors could successfully be used.

关键词： campaniform sensillum strain displacement compliance hole remote sensing fibrous composite

Multi-Scale Compliant Foot Designs and Fabrication for Use with a Spider-Inspired Climbing Robot

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2008年第3期5卷 189-196页

作者： Dan Sameoto carlo Menon MENRvA Group School of Engineering Science Simon Fraser University Burnaby BC V5A 1S6 Canada

Climbing robots are of potential use for surveillance, inspection and exploration in different environments. In particular, the use of climbing robots for space exploration can allow scientists to explore environments too challenging for traditional wheeled designs. To adhere to surfaces, biomimetic dry adhesives based on gecko feet have been proposed. These biomimetic dry adhesives work by using multi-scale compliant mechanisms to make intimate contact with different surfaces and adhere by using van der Waals forces. Fabrication of these adhesives has frequently been challenging however, due to the difficulty in combining macro, micro and nanoscale compliance. We present an all polymer foot design for use with a hexapod climbing robot and a fabrication method to improve reliability and yield. A high strength, low-modulus silicone, TC-5005, is used to form the foot base and microscale fibres in one piece by using a two part mold. A macroscale foot design is produced using a 3D printer to produce a base mold, while lithographic definition of microscale fibres in a thick photoresist forms the ＇hairs＇ of the polymer foot. The adhesion of the silicone fibres by themselves or attached to the macro foot is examined to determine best strategies for placement and removal of feet to maximize adhesion. Results demonstrate the successful integration of micro and macro compliant feet for use in climbing on a variety of surfaces.

关键词： biomimetics dry adhesive gecko climbing robot MEMS silicone

Performance of Forearm FMG and sEMG for Estimating Elbow, Forearm and Wrist Positions

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2017年第2期14卷 284-295页

作者： Zhen Gang Xiao carlo Menon Menrva Research Group Schools of Mechatronic Systems Engineering and Engineering Science Simon Fraser University British Columbia V3T0A3 Canada

The ability to track upper extremity movement during activity of daily living has the potential to facilitate the recovery of individuals with neurological or physical injuries. Hence, the use of Surface Electromyography （sEMG） signals to predict upper extremity movement is an area of interest in the research community. A less established technique, Force Myography （FMG）, which uses force sensors to detect forearm muscle contraction patterns, is also able to detect some movements of the arm. This paper investigates the comparative performance of sEMG and FMG when predicting wrist, forearm and elbow positions using signals extracted from the forearm only. Support vector Machine （SvM） and Linear Discriminant Analysis （LDA） classifiers were used to evaluate the prediction performance of both FMG and sEMG data. Ten healthy volunteers participated in this study. Under a cross validation across a repetition evaluation scheme, the SvM classifier obtained averaged accuracies of 84.3%, 82.4% and 71.0%, respectively, for predicting elbow, forearm and wrist positions using FMG; while sEMG yielded 75.4%, 83.4% and 92.4% accuracies for predicting the same respective positions. The accuracies obtained using SvM are slightly, but statistical significantly, higher than the ones obtained using LDA. However, the trends on the classification performances between FMG and sEMG are consistent. These results also indicate that the forearm FMG pattern is highly influenced by the change of elbow position, while the forearm sEMG is less subjected to the change. Overall, both forearm FMG and sEMG techniques provide abundant information that can be utilized for tracking the upper extremity movements.

关键词： Surface Electromyography (sEMG) Force Myography (FMG) classification limb movement activity monitoring,upper extremity

Bioinspired Dry Adhesive Materials and Their Application in Robotics： A Review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2016年第2期13卷 181-199页

作者： Yasong Li Jeffrey Krahn carlo Menon MENRvA Research Group School of Engineering Science Simon Fraser University 8888 University Drive Burnaby BC V5A 1S6 Canada

Dry adhesives inspired from climbing animals, such as geckos and spiders, rely on van der Waals forces to attach to the opposing surface. Biological fibrillar dry adhesives have a hierarchical structure closely resembling a tree： the surface of the skin on the animal＇s feet is covered in arrays of slender micro-fibrils, each of which supports arrays of fibrils in submicron dimensions. These nano-meter size fibrils can conform closely to the opposing surfaces to induce van der Waals interaction. Bioinspired dry adhesives have been developed in research laboratories for more than a decade. To mimic the biological fibrillar adhesives, fibrillar structures have been prepared using a variety of materials and geometrical arrangements. In this review article, the mechanism and selected fabrication methods of fibrillar adhesives are summarized for future reference in adhesive development. Robotic applications of these bioinspired adhesives are also introduced in this article. various successful appli- cations of bioinspired fibrillar adhesives can shed light on developing smart adhesives for use in automation.

关键词： bioinspired gecko adhesive van der Waals forces biomimetic climbing robot bioinspired tape