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Vibration and Buckling Analyses of Sandwich Plates Containing Functionally Graded Metal Foam Core

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Acta Mechanica Solida Sinica 2022年第4期35卷 587-602页

作者： A.Garg H.d.Chalak L.Li M.-O.Belarbi R.Sahoo T.Mukhopadhyay department of Civil Engineering National Institute of TechnologyKurukshetraHaryana136119India department of Aerospace Engineering Indian Institute of TechnologyKanpurUttar Pradesh208016India State Key Lab of digital Manufacturing Equipment and Technology School of Mechanical Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Laboratoire de Génie Energétique et matériaux LGEMFacultéde la science et de lo TechnologieUniversitéde BiskraB.P.145R.P.07000BiskraAlgeria department of Civil Engineering Indian Institute of TechnologyBanaras Hindu UniversityVaranasiUttar Pradesh221005India

In the present work,free vibration and buckling analyses of sandwich plates with various functionally graded foam cores are carried *** cores are assumed to be made of metal,and three different configurations of the porous distribution in the core layer are taken into *** carry out a comparative study between the distributions of pores in the core foam,the mass of foam in all three cases is kept the *** vibration and buckling behaviors of skew plates are also analyzed as a part of the current *** principle of minimization of potential energy and Hamilton’s principle are used for the derivation of the governing equations,while a C-0 finite element-based higher-order zigzag formulation is developed to solve the free vibration and buckling *** influences of gradation laws,boundary conditions,skew angle and geometry of plates are studied in detail for the dynamic and stability *** is found that both the non-dimensional natural frequency and buckling load decrease with the increase in the thickness of the metal foam cores,while they show an increasing trend as the skew angle of the plate increases.

关键词： Sandwich plate Metal foam core Functionally graded core Finite element Skew plate

The Giant Radio Array for Neutrino detection(GRANd):Science and design

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Science China(Physics,Mechanics & Astronomy) 2020年第1期63卷 1-43页

作者： Jaime Alvarez-Muniz Rafael Alves Batista Aswathi Balagopal V. Julien Bolmont Mauricio Bustamante Washington Carvalho Jr. didier Charrier Ismael Cognard Valentin decoene Peter B.denton Sijbrand de Jong Krijn d.de Vries Ralph Engel Ke Fang Chad Finley Stefano Gabici Quan Bu Gou Jun Hua Gu Claire Guépin Hong Bo Hu Yan Huang Kumiko Kotera Sandra Le Coz Jean-Philippe Lenain Guo Liang Léü Olivier Martineau-Huynh Miguel Mostafá Fabrice Mottez Kohta Murase Valentin Niess Foteini Oikonomou Tanguy Pierog Xiang Li Qian Bo Qin duan Ran Nicolas Renault-Tinacci Markus Roth Frank G.Schroder Fabian Schüssler Cyril Tasse Charles Timmerman matías Tueros Xiang Ping Wu Philippe Zarka Andreas Zech B.Theodore Zhang Jian Li Zhang Yi Zhang Qian Zheng Anne Zilles departamento de Fisica de Particulas&lnstituto Galego de Fisica de Altas Enerxias Universidad de Santiago de CompostelaSantiago de Compostela 15782Spain Instituto de Astronomia Geofisica e Ciencias AtmosfericasUniversidade de Sao PauloSao Paulo-SP 05508-090Brazil department of Physics-Astrophysics University of OxfordDWBOxford 0X13RHUK Institute of Experimental Particle Physics(ETP) Karlsruhe Institute of Technology(KIT)Karlsru he D-76021Germany Laboratoire de Physique Nucleeaire et de Hautes Energies(LPNHE) Sorbonne UniversiteUniversite Paris DiderotSorbonne Paris CiteCNRS place Jussieu F-75252Paris Cedex 5France Niels Bohr International Academy and dARK Niels Bohr InstituteCopenhagen 2100Denmark discovery Center Niels Bohr InstituteCopenhagen 2100Denmark Center for Cosmology and AstroParticle Physics(CCA.PP)&department of Physics Ohio State UniversityColumbus OH 43210USA Universidade de Santiago de Compostela Santiago de Compostela 15782Spain 0SUBATECH Institut Mines-Telecom Atlantique-CNRS/IN2P3-Universite de NantesNantes 44300France Laboratoire de Physique et Chimie de KEnvironnement et de VEspace LPC2E CNRS-Universite d'Orleans Orleans F-45071France Station de Radioastronomie de Nancay Observatoire de ParisCNRS/INSU F-18330 NangayFrance Sorbonne Universite UMR 7095Institut d'Astrophysique de Paris98 bis bd AragoParis 75014France Institute for mathematics Astrophysics and Particle Physics(IMAPP)Radboud UniversiteitNijmegen 6500Netherlands Nationaal Instituut voor Kemfysica en Hoge Energie Fysica(NIKHEF) Amsterdam NL-1009Netherlands IIHE/ELEM Vrije Universiteit BrusselPleinlaan 2Brussels 1050Belgium Institute for Nuclear Physics(IKP) Karlsruhe Institute of Technology(KIT)Karlsruhe D-76021Germany Einstein Fellow Stanford UniversityStanford CA 94305USA department of Astronomy University of MarylandCollege Park MD 20742-2421USA Joint Space-Science Institute College Park MD 20742-2421USA Oskar Klein Centre Stockholm UniversityStockholm SE-10691Sweden department of Phy

The Giant Radio Array for Neutrino detection(GRANd)is a planned large-scale observatory of ultra-high-energy(UHE)cosmic particles,with energies exceeding 10~8 Ge *** goal is to solve the long-standing mystery of the origin of UHE cosmic *** do this,GRANd will detect an unprecedented number of UHE cosmic rays and search for the undiscovered UHE neutrinos and gamma rays associated to them with unmatched *** will use large arrays of antennas to detect the radio emission coming from extensive air showers initiated by UHE particles in the *** design is modular:20 separate,independent sub-arrays,each of 10000 radio antennas deployed over 10000 km^2.A staged construction plan will validate key detection techniques while achieving important science goals *** we present the science goals,detection strategy,preliminary design,performance goals,and construction plans for GRANd.

关键词： radio telescopes neutrinos in astronomical observations cosmic rays in astronomical observations radiowave radiation:sources galactic and extragalactic cosmic rays:galactic and extragalactic

Identification of predictive MRI and functional biomarkers in a pediatric piglet traumatic brain injury model

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Neural Regeneration Research 2021年第2期16卷 338-344页

作者： Hongzhi Wang Emily W.Baker Abhyuday Mandal Ramana M.Pidaparti Franklin d.West Holly A.Kinder department of Statistics University of GeorgiaAthensGAUSA Regenerative Bioscience Center University of GeorgiaAthensGAUSA department of Animal and dairy Science University of GeorgiaAthensGAUSA College of Engineering University of GeorgiaAthensGAUSA

Traumatic brain injury(TBI) at a young age can lead to the development of long-term functional impairments. Severity of injury is well demonstrated to have a strong influence on the extent of functional impairments;however, identification of specific magnetic resonance imaging(MRI) biomarkers that are most reflective of injury severity and functional prognosis remain elusive. Therefore, the objective of this study was to utilize advanced statistical approaches to identify clinically relevant MRI biomarkers and predict functional outcomes using MRI metrics in a translational large animal piglet TBI model. TBI was induced via controlled cortical impact and multiparametric MRI was performed at 24 hours and 12 weeks post-TBI using T1-weighted, T2-weighted, T2-weighted fluid attenuated inversion recovery, diffusion-weighted imaging, and diffusion tensor imaging. Changes in spatiotemporal gait parameters were also assessed using an automated gait mat at 24 hours and 12 weeks post-TBI. Principal component analysis was performed to determine the MRI metrics and spatiotemporal gait parameters that explain the largest sources of variation within the datasets. We found that linear combinations of lesion size and midline shift acquired using T2-weighted imaging explained most of the variability of the data at both 24 hours and 12 weeks post-TBI. In addition, linear combinations of velocity, cadence, and stride length were found to explain most of the gait data variability at 24 hours and 12 weeks post-TBI. Linear regression analysis was performed to determine if MRI metrics are predictive of changes in gait. We found that both lesion size and midline shift are significantly correlated with decreases in stride and step length. These results from this study provide an important first step at identifying relevant MRI and functional biomarkers that are predictive of functional outcomes in a clinically relevant piglet TBI model. This study was approved by the University of Georgia I

关键词： controlled cortical impact gait analysis linear regression magnetic resonance imaging motor function pediatric pig model principal component analysis traumatic brain injury

Influence of surface roughness on the color of dental-resin composites

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2011年第7期12卷 552-562页

作者： Razvan GHINEA Laura UGARTE-ALVAN Ana YEBRA Oscar E.PECHO Rade d.PARAVINA Maria del Mar PEREZ department of Optics Faculty of ScienceUniversity of Granada department of Stomatology Faculty of OdontologyUniversity of Granada Houston Center for Biomaterials and Biomimetics & department of Restorative dentistry and Biomaterials University of Texas Dental Branch at Houston

This study deals with the influence of surface roughness on the color of resin *** resin composites (microfilled,hybrid,and microhybrid) were each polished with 500-grit,1 200-grit,2 000-grit,and 4 000-grit SiC *** roughness parameter (Ra) was measured using a Plμ confocal microscope,and field-emission scanning electron microscope (Fe-SEM) images were used to investigate filler *** was measured using a spectroradiometer and a d65 standard illuminant (geometry diffuse/0° specular component excluded (SCE) mode).Surface roughness decreased with grit number and was not influenced by filler size or size distribution.A significant influence of Ra on lightness (L*) was *** increased with decreases in roughness,except for specimens that underwent polishing procedure 4 (PP4;500-grit,1 200-grit,2 000-grit,and 4 000-grit SiC papers consecutively).Generally,it was found that surface roughness influenced the color of resin *** composites that underwent PP1 (500-grit SiC paper) exhibited significant differences in chroma (C*),hue (h°),and lightness (L*) compared to composites that underwent PP3 (500-grit,1 200-grit,and 2 000-grit SiC papers consecutively) and *** difference (E*) between the polishing procedures was within acceptability thresholds in dentistry.

关键词： Color measurement dental resin composites Roughness

KCl:Eu^(2+) as a solar UV-C radiation dosimeter. Optically stimulated luminescence and thermoluminescence analyses

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Journal of Rare Earths 2009年第4期27卷 579-583页

作者： I.Aguirre de Cárcer H.L.d'Antoni M.Barboza-Flores V.Correcher F.Jaque departamento Física de materiales Universidad Autónoma Madrid Spain NASA Ames Research Center Moffett Field California USA Centro de Investig ción en Física Universidad de Sonora México Centro Investigaciones Energía y Medioambientales (CIEmat) Madrid Spain

The KCI：Eu2＋ system response to UV-C was investigated by analyzing the optically stimulated luminescence （OSL） and ther- mo-luminescence （TL） signal produced by ultraviolet light exposure at room temperature. It was found that after UV-C ***, OSL was produced on a wide band of visible wavelengths with decay time that varied by several orders of magnitude depending on the Eu2＋ aggregation state. In spite of the low intensity of solar UV-C reaching the Earth＇s surface in Madrid （40° N, 700 m a.s.1.）, it was possible to measure the UV-C radiation dose at 6：48 solar time by using the TL response of the KCI：Eu2＋ system and differentiate it from the ambient beta radiation dose.

关键词： thermo-luminescence rare-earth-doped alkali halides solar ultraviolet dosimeter environmental radiation

Synthesis and Enhanced Superplasticity of the Zirconia-dispersed Alumina Nanocomposite

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Journal of materials Science & Technology 2005年第1期21卷 79-82页

作者： Guoqing CHEN, Kaifeng ZHANG, Wenbo HAN and Junting LUOSchool of materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, ChinaProf., Ph.d., Sch. of mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

A series of alumina-zirconia composites with various grain sizes were prepared from the nano-sized powders with different agglomerations. Microstructural analysis of the sintered compacts indicates that the as-sintered material is a typical intra/inter granular nanocomposite with uniform distribution of the zirconia grains in the alumina matrix. Superplastic deep drawing test under different conditions demonstrates that dense Al2O3/ZrO2 samples with average grain size of 230 nm can be elongated to a dome height of at least 12 mm at the punch rate of 0.6 mm·min-1 at 1400℃. Further drawing tests show that for the composites with larger grain size, such elongation cannot be achieved at such a strain rate.

关键词： Nanocomposite Synthesis Microstructure Superplasticity

Superplastic Forming and diffusion Bonding for Sandwich Structure of Ti-6Al-4V Alloy

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Journal of materials Science & Technology 2005年第1期21卷 60-62页

作者： Wenbo HAN, Kaifeng ZHANG, Guofeng WANG and Xiaojun ZHANGSchool of materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, ChinaProf., Ph.d., Sch. of mat. Sci. and Eng. Harbin Inst. of Technol. Harbin 150001 China

Superplastic forming and diffusion bonding (SPF/dB) is a well-established process for the manufacture of components almost exclusively from Ti-6AI-4V sheet material. The sandwich structure of Ti-6AI-4V alloy is investigated. The effects of the microstructure on the SPF/dB process were discussed. The microstructure at the interfaces and the distribution of thickness were researched.

关键词： Superplastic forming diffusion bonding Sandwich structure TI-6A1-4V alloy

Wettability and Bonding between Ni and Ti(C,N)with Multiple Carbide Additions

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Journal of materials Science & Technology 2005年第1期21卷 53-59页

作者： Ning LIU, Minghai CHEN, Yudong XU, Jie ZHOU and Min SHIdepartment of materials Science and Engineering, Hefei University of Technology, Hefei 230009, ChinaProf., Ph.d. dept. of mat. Sci. and Eng. Hefei Univ. of Technol. Hefei 230009 China

The wettability and bonding in Ni/Ti(C, N) systems with multiple carbide additions were studied by sessile drop technique and vacuum brazing technique, respectively. The phase characterizations of substrates and fracture surfaces were conducted by XRd. The microstructures at metal/ceramic interfaces and fracture surfaces were observed via SEM in back scattered mode and second electron mode, respectively. Furthermore, an X-ray energy-dispersive spectrometer (EdS) attached to SEM was used to study the elements diffusion in interfacial regions. The results reveal that diffusion and dissolution mechanism controlled reactive wetting takes place in the system in high temperature wetting. Results also show that the contact angles decrease with multiple carbide additions, and the effect of multiple carbide additions is stronger than that of single additions. The contact angle reaches the lowest value in the lowest TiC content case. The enhancement of the wettability is due to alloying procedure during high tempe

关键词： Interfaces diffusion Ti(C, N)-based cermets Wettability Bonding

Unveiling the Residual Stresses,Local Micromechanical Properties and Crystallographic Texture in a Ti-6Al-4V Weld Joint

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Acta Metallurgica Sinica(English Letters) 2021年第7期34卷 997-1006页

作者： B.Mehdi R.Badji V.Ji B.Alili d.Bradai W.Bedjaoui F.deschaux-Beaume F.Brisset Laboratoire de Physique des matériaux Facul téde PhysiqueUniversitéDes Sciences Et de La Technologie Houari Boumediene16111 AlgerAlgérie Research Center in Industrial Technologies CRTI P.O.Box64CheragaAlgeria ICMMO/SP2M UniversitéParis-Saclay LMGC University of MontpellierCNRSMontpellierFrance

In this work,the micromechanical properties,crystallographic texture,welding residual stresses and their evolution after plastic strain were investigated in a Ti-6Al-4V alloy tungsten inert gas weld *** was found that the welding process affected the Young modulus and microhardness values in bothαandβphases in the different regions of the weld *** highest microhardness and Young modulus values of a phase were recorded in the heat-affected zone,whereas the highest values of these characteristics for theβphase were found in the fusion zone(FZ).The change in the micro mechanical properties was accompanied by a change in the crystallographic texture components of the dominant a phase from(0001)and(11-20)components in the base material to(10-10)and(11-20)components in the *** introduction of tensile testing resulted in a continuous stress relaxation and improved the weld joint performances.

关键词： Ti-6Al-4 V Tungsten inert gas(TIG)weld Residual stress Local mechanical properties Crystallographic texture