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developments in Processing of Functionally Gradient Metals and Metal–ceramic composites:A Review

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Acta Metallurgica Sinica(English Letters) 2014年第5期27卷 825-838页

作者： t.P.d.Rajan B.c.Pai Materials Science and technology division CSIR-National Institute for Interdisciplinary Science and TechnologyIndustrial Estate PO

Functionally gradient/graded materials （FGMs）, an emerging new class of materials, are the outcome of the recent innovative concepts in materials technology. FGMs are in their early stages of evolution and expected to have a strong impact on the design and development of new components and structures with better performance. FGMs exhibit gradual transitions in the microstructure and/or the composition in a specific direction, the presence of which leads to variation in the functional performance within a part. the presence of gradual transitions in material composition in FGMs can reduce or eliminate the deleterious stress concentrations and result in a wide gradation of physical and/or chemical properties within the material. Functionally graded metal-ceramic composites are also getting the attention of the researchers. Among the fabrication routes for FGMs such as chemical vapour deposition, physical vapour deposition, the sol-gel technique, plasma spraying, molten metal infiltration, self propagating high temperature synthesis, spray forming, centrifugal casting, etc., the ones based on solidification route are preferred for FGMs because of their economics and capability to make large size products. the present paper discusses and compares various solidification processing tech- niques available for the fabrication of functionally gradient metals and metal-ceramic composites and lists their properties and possible applications. the other processing methods are briefly described.

关键词： Functionally gradient materials Solidification Aluminium centrifugal casting Infiltration

Impact of Pollutant concentration and Particle deposition on the Radiative Flow of casson-Micropolar Fluid between Parallel Plates

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computer Modeling in Engineering & Sciences 2025年第1期142卷 665-690页

作者： Ghaliah Alhamzi Badr Saad t.Alkahtani Ravi Shanker dubey Vinutha Kalleshachar Neelima Nizampatnam department of Mathematics and Statistics College of ScienceImam Mohammad Ibn Saud Islamic University(IMSIU)Riyadh11564Saudi Arabia department of Mathematics College of ScienceKing Saud UniversityRiyadh11989Saudi Arabia department of Mathematics Amity School of Applied SciencesAmity University RajasthanJaipur302002RajasthanIndia department of Studies in Mathematics Davangere UniversityDavangere577002India department of Electronics and communication Engineering Amrita School of EngineeringAmrita Vishwa VidyapeethamBengaluru560035India

Assessing the behaviour and concentration of waste pollutants deposited between two parallel plates is essential for effective environmental *** the effectiveness of treatment methods in reducing pollution scales is made easier by analysing waste discharge *** waste discharge concentration analysis is useful for assessing how effectively wastewater treatment techniques reduce pollution *** study aims to explore the casson micropolar fluid flow through two parallel plates with the influence of pollutant concentration and thermophoretic particle *** explore the mass and heat transport features,thermophoretic particle deposition and thermal radiation are *** governing equations are transformed into ordinary differential equations with the help of suitable similarity *** Runge-Kutta-Fehlberg’s fourthfifth order technique and shooting procedure are used to solve the reduced set of equations and boundary *** integration of a neural network model based on the Levenberg-Marquardt algorithm serves to improve the accuracy of predictions and optimize the analysis of *** outcomes are displayed to analyze the characteristics of the relevant dimensionless parameters in the current *** reveal that concentration upsurges as the micropolar parameter *** concentration reduces with an upsurge in the thermophoretic *** upsurge in the external pollutant source variation and the local pollutant external source parameters enhances mass *** surface drag force declines for improved values of porosity and micropolar parameters.

关键词： Micropolar fluid thermal radiation porous medium thermophoretic particle deposition waste discharge concentration

combining spatial modelling and radar to identify and protect avian migratory hot-spots

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current Zoology 2014年第5期60卷 680-691页

作者： Mark dESHOLM Rashpal GILL thomas BOVItH Anthony d. fox department of Bioscience Aarhus University Kalo Grenavej 14 8410 Ronde Denmark BirdLife denmark Vesterbrogade 140 1620 Copenhagen V Denmark Research department Danish Meteorological Institute Lyngbyvej 100 2100 Copenhagen O Denmark

Migrating landbirds are known to follow coast lines and concentrate on peninsulas prior to crossing water bodies, es- pecially during daylight but also at night, creating enhanced potential collision hazards with man-made objects. Knowing where these avian migration ＂hot-spots＂ occur in time and space is vital to improve flight safety and inform the spatial planning process （e.g. environmental assessments for offshore windfarms）. We developed a simple spatial model to identify avian migration hot- spots in coastal areas based on prevailing migration orientation and coastline features known, from visual and radar observations, to concentrate migrating landbirds around land masses. Regional scale model validation was achieved by combining nocturnal passerine movement data gathered from two tier radar coverage （long-range dual-polarization doppler weather radar and short- range marine surveillance radar） and standardised bird ringing. Applied on a national scale, the model correctly identified the ten most important danish coastal hot-spots for spring migrants and predicted the relative numbers of birds that concentrated at each site. these bird numbers corresponded well with historical observational data. Here, we provide a potential framework for the es- tablishment of the first three-dimensional avian airspace sanctuaries, which could contribute to more effective conservation of long-distance migratory birds [current Zoology 60 （5）： 680-691, 2014].

关键词： Radar ornithology Migration Orientation conservation Spatial model

Performance analysis of InSb based QWFEt for ultra high speed applications

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Journal of Semiconductors 2015年第1期36卷 60-63页

作者： t.d.Subash t.Gnanasekaran c.divya K.N.S.K college of Engineering Nagercoil-629901 India department of It RMK College of Engineering and Technology 629401 India centre for It & Eng Manonmaniam Sundaranar University 627012 India

An indium antimonide based QWFEt（quantum well field effect transistor） with the gate length down to 50 nm has been designed and investigated for the first time for L-band radar applications at 230 GHz. QWFEts are designed at the high performance node of the International technology Road Map for Semiconductors（ItRS）requirements of drive current（Semiconductor Industry Association 2010）. the performance of the device is investigated using the SYNOPSYS cAd（tcAd） software. In Sb based QWFEt could be a promising device technology for very low power and ultra-high speed performance with 5–10 times low dc power dissipation.

关键词： QWFEt InSb gate length cut-off frequency short-channel effects

Near resonance vibration isolation on a levered-dual response(LEdAR)coulomb-damped system by differential preloads/offsets in linear springs

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Applied Mathematics and Mechanics(English Edition) 2024年第6期45卷 1033-1050页

作者： t.I.tOLUWALOJU c.K.tHEIN d.HALIM department of Mechanical Materials and Manufacturing EngineeringUniversity of Nottingham Ningbo ChinaNingbo 315100Zhejiang ProvinceChina Nottingham Ningbo china Beacons of Excellence Research and Innovation Institute University of Nottingham Ningbo ChinaNingbo 315048Zhejiang ProvinceChina

the levered-dual response(LEdAR)coulomb-damped system attains near resonant vibration isolation by differential preloads/offsets in linear *** takes the advantages of both the preloads/offsets in linear springs and the guiderail friction for realizing different levels of vibration *** isolation capacities are investigated on the strategies with both the horizontal and vertical guiderails,with the horizontal rail only,and without *** compressive preloads generally result in the consumption of most of the initial excitation energy so as to overcome the potential *** isolation onsets at the frequency ratio of 1∓0.095 on the left-hand side(LHS)and the right-hand side(RHS)of the lever are relative to the load plate *** observed near resonant isolation thus makes the LEdAR system a candidate for the isolation of the mechanical systems about resonance while opening a path for simultaneous harvesterisolation functions and passive functions at extreme frequencies.

关键词： lever ratio coulomb damping preload tension/compression isolation band/depth offset potential

Oligodendroglial heterogeneity in health,disease,and recovery:deeper insights into myelin dynamics

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Neural Regeneration Research 2025年第11期20卷 3179-3192页

作者： Pieter-Jan Serneels Julie d.de Schutter Lies de Groef Lieve Moons Steven Bergmans KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionNeural Circuit Development&Regeneration Research GroupLeuvenBelgium KU Leuven Leuven Brain InstituteDepartment of BiologyAnimal Physiology and Neurobiology DivisionCellular Communication&Neurodegeneration Research GroupLeuvenBelgium

decades of research asserted that the oligodendroglial lineage comprises two cell types:oligodendrocyte precursor cells and ***,recent studies employing single-cell RNA sequencing techniques have uncovered novel cell states,prompting a revision of the existing *** forward,the oligodendroglial lineage should be delineated into five distinct cell states:oligodendrocyte precursor cells,committed oligodendrocyte precursor cells,newly formed oligodendrocytes,myelin-forming oligodendrocytes,and mature *** new classification system enables a deeper understanding of the oligodendroglia in both physiological and pathological *** this uniform terminology will facilitate comparison and integration of data across ***,including the consolidation of findings from various demyelinating models,is essential to better understand the pathogenesis of demyelinating ***,comparing injury models across species with varying regenerative capacities can provide insights that may lead to new therapeutic strategies to overcome remyelination ***,by standardizing terminology and synthesizing data from diverse studies across different animal models,we can enhance our understanding of myelin pathology in central nervous system disorders such as multiple sclerosis,Alzheimer's disease,and amyotrophic lateral sclerosis,all of which involve oligodendroglial and myelin dysfunction.

关键词： animal models demyelination fish mammals multiple sclerosis myelin neurodegeneration oligodendrocytes oligodendroglial lineage remyelination

Fullwave doppler reflectometry simulations for density turbulence spectra in ASdEX Upgrade using GENE and IPF-Fd3d

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Plasma Science and technology 2020年第6期22卷 41-48页

作者： c LEcHtE G d cONWAY tGÖRLER t HAPPEL the ASdEX Upgrade team Institute of Interfacial Process Engineering and Plasma technology IGVP Universität StuttgartD-70569 StuttgartGermany Max-Planck-Institute for Plasma Physics D-85748 GarchingGermany 不详

doppler reflectometry is an important microwave diagnostic for turbulent fusion plasmas.A microwave beam is scattered off density fluctuations,with wavenumbers according to incident frequency and relative *** way,a density fluctuation spectrum is ***,the correspondence between fluctuation power and scattered microwave power is strongly *** these processes numerically therefore requires fullwave simulations(IPF-Fd3 d),with density fluctuations supplied by a separate plasma turbulence code(GENE).Earlier such attempts suffered from the low number of data points in the‘interesting’part of the spectrum,where a power law had to be fitted to 4 or 5 *** has been overcome with recent simulations,which now show a much better agreement with experimental data.

关键词： plasma diagnostics doppler reflectometry simulation microwaves

can an 8^(th) grade student learn point of care ultrasound?

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World Journal of Emergency Medicine 2019年第2期10卷 109-113页

作者： Alexander S.Kwon Shadi Lahham John c.fox Sage Hill School department of Emergency Medicine UC Irvine Medical Center UC Irvine School of Medicine

BAcKGROUNd: Point-of-care ultrasound has gained widespread use in developing countries due to decreased cost and improved telemedicine capabilities. Ultrasound training, specifi cally image acquisition skills, is occurring with more frequency in non-medical personnel with varying educational levels in these underdeveloped areas. this study evaluates if students without a high school education can be trained to acquire useful FASt images, and to determine if an 8^(th) grade student can teach peers these ***: the 8^(th) grade students at a small middle school were divided into two groups. One group received training by a certified medical sonographer, while the other group received training by a peer 8^(th) grade student trainer who had previously received training by the sonographer. After training, each student was independently tested by scanning the four FASt locations. A blinded ultrasound expert evaluated these images and deemed each image adequate or inadequate for clinical ***: Eighty video image clips were obtained. the overall image adequacy rate was 74%. the splenorenal window had the highest rate at 95%, followed by retrovesical at 90%, hepatorenal at 75%, and subxiphoid cardiac at 35%. the adequacy rate of the sonographer-trained group was 78%, while the adequacy rate of the student-trained group was 70%. the difference in image adequacy rate between the two groups was not signifi cant(P-value 0.459).cONcLUSION: the majority of 8^(th) graders obtained clinically adequate FASt images after minimal training. Additionally, the student-trained group performed as well as the sonographer-trained group.

关键词： Point of care ultrasound FASt Image acquisition training

Microstructure, Mechanical and corrosion Properties of AlcocrFeNi High-Entropy Alloy Prepared by Spark Plasma Sintering

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Acta Metallurgica Sinica(English Letters) 2020年第7期33卷 937-946页

作者： P.F.Zhou d.H.Xiao t.c.Yuan National Key Laboratory of Science and technology for National defence on High-strength Structural Materials Central South UniversityChangsha 410083China

AlcocrFeNi is one of the most widely studied alloy systems in the high-entropy alloy(HEA) area due to the interesting microstructure and mechanical *** this study,the AlcocrFeNi alloy was prepared using spark plasma sintering(SPS) with pre-alloy powders obtained through gas ***,the sintered samples were annealed at 700,800 and900℃,and the effect of annealing temperature on the microstructure,mechanical and corrosion properties was *** results show that phase formation takes place during annealing process with the new phase(σ) and some nano scale Bcc precipitates *** size and quantity of the nanoscale precipitates increase with increasing annealing *** twin is also observed after annealing at 900℃.the annealing temperature has an obvious effect on the mechanical properties and corrosion resistance of the spark plasma sintered AlcocrFeNi *** the annealing temperature is 700℃,the hardness,yield strength and fracture strength reach the maximum with the value of 545 HV,1430 MPa and 2230 MPa,*** compressive ratio reaches the maximum of 17.2%,with the annealing temperature increasing to 800℃.the corrosion resistance of the samples decreases with increasing the annealing temperature.

关键词： alloy corrosion microstructure