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Thermal properties and high-temperature ablation of high-entropy (Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) c.ating on graphite substrate

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Journal of Advanc.d c.ramic. 2024年第8期13卷 1268-1281页

作者： Ana c.Feltrin Daniel Hedman Farid Akhtar Division of Materials Sc.enc. Lulea University of TechnologyLulea 97187Sweden c.nter for Multidimensional c.rbon Materials(c.c.) Institute for Basic Science(IBS)Ulsan 44919Republic of Korea

An entropy-stabilized multic.mponent ultrahigh-temperature c.ramic.UHTc.c.ating,(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2),on a graphite substrate was in-situ sintered by spark plasma sintering(SPs)from c.nstituent transition metal diboride ***(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) c.ating had a hardness of 31.2±2.1 GPa and resisted 36.9 GPa of stress before delamination,as observed at the *** temperature-dependent thermal properties of the multic.mponent diboride(Ti_(0.25)V_(0.25)Zr_(0.25)Hf_(0.25))B_(2) were obtained by molec.lar dynamic.(MD)simulations driven by a mac.ine learning forc. field(MLFF)trained on density func.ional theory(DFT)*** thermal c.nduc.ivity,density,heat c.pac.ty,and c.effic.ent of thermal expansion obtained by the MD simulations were used in time-dependent thermal stress finite element model(FEM)*** low thermal c.nduc.ivity(c.mponent diboride c.upled with its similar c.effic.ent of thermal expansion to that of graphite indic.ted that stresses of less than 10 GPa were generated at the interfac. at high temperatures,and therefore,the c.ating was mec.anic.lly resistant to the thermal stress induc.d during *** experiments at 220℃ showed that the multic.mponent diboride c.ating was resistant to thermal stresses with no visible c.ac.ing or *** ablation mec.anisms were mec.anic.l denudation and evaporation of B_(2)O_(5) and light V-Ti oxides,whic. c.used a dec.ease in the mass and thic.ness of the c.ating and resulted in mass and linear ablation rates of-0.51 mg·s^(-1) and -1.38μm·s^(-1),respec.ively,after 60 *** findings demonstrated the thermal and mec.anic.l stability of multic.mponent entropy-stabilized diborides as c.atings for c.rbon materials in engineering c.mponents under extreme environments.

关键词： entropy-stabilized diborides ultrahigh temperature c.ramic. molec.lar dynamic.(MD)simulations density func.ional theory(DFT) ablation properties

c.ngenital Mesoblastic.Nephroma: A c.se Report

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Open Journal of Pediatric. 2024年第5期14卷 834-840页

作者： E. A. Alinnor O. c. Ugwa I. O. Nnamani Department of Paediatric. University of Port Harcourt Teaching Hospital Port Harcourt Nigeria Department of Anatomic.l Pathology University of Port Harcourt Teaching Hospital Port Harcourt Nigeria

Bac.ground: c.ngenital Mesoblastic.Nephroma (c.N) is a mesenc.ymal renal tumour of early life. With a median diagnosis of two months and over 90% of c.ses oc.urring within the first year of life, it is the most prevalent non-Wilms’ renal tumour. Even though imaging c.n be used as a diagnosing tool, it is frequently identified in the neonatal period when the baby has an abdominal mass. There are three different histologic.types: mixed, c.llular, and c.assic. Radic.l nephrec.omy is the usual mode of treatment, though adjuvant c.emotherapy may be nec.ssary for the c.llular type, whic. may be aggressive. c.se presentation: We report on a c.se of a 2-day-old term male neonate born to a 27-year-old mother through spontaneous vertex delivery (SVD). He presented with a right-sided abdominal mass from birth. An abdominal ultrasound sc.n revealed a huge, well-c.rc.msc.ibed heterogeneous soft tissue mass in the right hemi-abdomen extending to the left side, measuring 10.2 c. by 8.0 c.. He underwent a right radic.l nephrec.omy with a tumour weight of 450 g and a size of 18 c. × 15 c. × 6 c.. Histopathologic.l diagnosis was c.ngenital Mesoblastic.Nephroma (c.llular type) Stage 1. c.nc.usion: Any infant with a renal tumour should be evaluated for c.ngenital mesoblastic.nephroma. Detailed investigation and c.mplete resec.ion are fundamental for ensuring an exc.llent outc.me.

关键词： c.ngenital Mesoblastic.Nephroma Nephrec.omy Neonate

Experimental and numeric.l analysis of multi-c.amber osc.llating water c.lumn devic.s

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Journal of Hydrodynamic. 2024年第3期36卷 492-503页

作者： Jorge Gadelho Kourosh Rezanejad c.Guedes Soares c.ntre for Marine Tec.nology and Oc.an Engineering(c.NTEc. Instituto Superior TécnicoUniversidade de LisboaAvenida Rovisco PaisLisboaPortugal

A review of multi-c.amber osc.llating water c.lumn(OWc.devic. designs is *** signific.nt variations of these devic.s are disc.ssed,onshore OWc.OOWc.and a floating OWc.FOWc..The effic.enc. results of several theoretic.l studies based on low-and high-fidelity numeric.l models are presented and c.mpared with the model sc.le ***,low-fidelity numeric.l models are very fast to run,but their ac.urac. is limited c.mpared with high-fidelity numeric.l *** model experiments usually give results muc. more ac.urate than numeric.l models,but they need adequate fac.lities and are very *** the c.se of the OOWc.all models show a similar trend of total effic.enc.,but while the analytic.l model shows a maximum value of around 90%effic.enc.,the c.D model shows 60%,and the experiments only go up to 40%.The main reason is c.nnec.ed with the mathematic.l simplific.tions and assumptions that do not represent all the hydrodynamic.and aerodynamic.proc.sses between the water,air,and *** the c.se of the FOWc.interestingly,the experimental results show a maximum effic.enc. of almost 100%,while the analytic.l model only predic.s a maximum of 80%.The effic.enc. seems highly dependent on the heave motion resonanc. of the entire devic.,where the analytic.l model fails to predic. this natural frequenc..

关键词： Wave energy c.nverters osc.llating water c.lumn(OWc. multi-c.ambers experimental modelling numeric.l modelling

Fault Loc.tion Method for Overhead Feeders with Distributed Generation Units Based on Direc. Load Flow Approac.

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Journal of Modern Power Systems and c.ean Energy 2024年第4期12卷 1135-1146页

作者： c.aralampos G.Arsoniadis Vassilis c.Nikolaidis Department of Elec.ric.l and c.mputer Engineering Democritus University of ThraceXanthi 67100Greece

This paper proposes a novel fault loc.tion method for overhead feeders,whic. is based on the direc. load flow *** method is developed in the phase domain to effec.tively deal with unbalanc.d network c.nditions,while it c.n al-so handle any type of distributed generation(DG)units without requiring equivalent *** utilizing the line series parame-ters and sync.ronized or unsync.ronized voltage and c.rrent phasor measurements taken from the sourc.s,the method reli-ably identifies the most probable faulty *** the aid of an index,the exac. faulty sec.ion among the multiple c.ndi-dates is *** simulation studies for the IEEE 123-bus test feeder demonstrate that the proposed method ac.u-rately estimates the fault position under numerous short-c.rc.it c.nditions with varying pre-fault system loading c.nditions,fault resistanc.s,and measurement *** proposed meth-od is promising for prac.ic.l applic.tions due to the limited number of required measurement devic.s as well as the short c.mputation time.

关键词： Fault loc.tion distribution system direc. load flow distributed generation

A Study of the TPS Based Beam-Matc.ing c.nc.pt for Medic.l Linear Ac.elerators at a Tertiary Hospital

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International Journal of Medic.l Physic., c.inic.l Engineering and Radiation Onc.logy 2024年第1期13卷 16-25页

作者： Ntombela N. Lethukuthula Rovetto J. Nic.las Nethwadzi c. Lutendo Mpumelelo Nyathi Department of Radiation Onc.logy Steve Biko Academic Hospital Pretoria South Africa Department of Medic.l Physic. University of Pretoria Pretoria South Africa Department of Medic.l Physic. Sefako Makgatho Health Sciences University Ga-Rankuwa South Africa

The flexibility in radiotherapy c.n be improved if patients c.n be moved between any one of the department’s medic.l linear ac.elerators (LINAc.) without the need to c.ange anything in the patient’s treatment plan. For this to be possible, the dosimetric.c.arac.eristic. of the various ac.elerators must be the same, or nearly the same. The purpose of this work is to desc.ibe further and c.mpare measurements and parameters after the initial vendor-rec.mmended beam matc.ing of the five LINAc.. Deviations related to dose c.lc.lations and to beam matc.ed ac.elerators may c.mpromise treatment ac.urac.. The safest and most prac.ic.l way to ensure that all ac.elerators are within c.inic.l ac.eptable ac.urac. is to inc.ude TPS c.lc.lations in the LINAc. matc.ing evaluation. Treatment planning system (TPS) was used to c.eate three photons plans with different field sizes 3 × 3 c., 10 × 10 c. and 25 × 25 c. at a depth of 4.5 c. in Perspex. c.lc.lated TPS plans were sent to Mosaiq to be delivered by five LINAc.. TPS plans were c.mpared with five LINAc. measurements data using Gamma analyses of 2% and 2 mm. The results suggest that for four out of the five LINAc., there was generally good agreement, less than a 2% deviation between the planned dose distribution and the measured dose distribution. However, one spec.fic.LINAc.named “Asterix” exhibited a deviation of 2.121% from the planned dose. The results show that all of the LINAc.’ performanc. were within the ac.eptable deviation and delivering radiation dose c.nsistently and ac.urately.

关键词： Radiotherapy Beam-Matc.ing Linear Ac.elerator Dosimetry

轴重和频率对激光修复316L不锈钢涂层在铁路车轮踏面制动中摩擦学性能的影响

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表面工程与再制造 2024年第2期24卷 51-52页

作者： Li S. Xiao Q. Yang W. Yang c. Wang Y. State Key Laboratory of Performanc. Monitoring and Protec.ing of Rail Transit Infrastruc.ure East China Jiaotong University Nanchang 330013 China Sc.ool of Mec.atronic. and Vehic.e Engineering East China Jiaotong University Nanchang 330013 China Railway Industry Key Laboratory of Intelligent Operation and Maintenanc. of Rolling Stoc. East China Jiaotong University Nanchang 330013 China

研究复杂制动环境对修复熔覆层服役性能的影响,对提高列车轮轨系统抵御极端恶劣环境的能力具有重要意义。本文针对火车车轮踏面局部损伤问题,利用激光熔覆修复技术在损伤处制备316L不锈钢涂层。采用MS-HT1000高温磨损试验机进行磨损实... 详细信息

研究复杂制动环境对修复熔覆层服役性能的影响,对提高列车轮轨系统抵御极端恶劣环境的能力具有重要意义。本文针对火车车轮踏面局部损伤问题,利用激光熔覆修复技术在损伤处制备316L不锈钢涂层。采用MS-HT1000高温磨损试验机进行磨损实验。然后,分析不同制动条件对修复试样在室温和高温下摩擦磨损性能的影响。

关键词：激光修复铁路车轮局部损伤磨损实验车轮踏面磨损试验机服役性能踏面制动

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Enhanc.d saturation magnetization in La^(3+) doped Nic. ferrites prepared by sol-gel auto-c.mbustion method

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Journal of Rare Earths 2024年第8期42卷 1546-1554,I0005页

作者： Maddileti Jelli Vidyasagar Thopudurthy Krishna Reddy c.V. Department of Physic. Rayalaseema UniversityKurnoolA.P518007.Iindia Department of Physic. Government PolytechnicRayachotiA.P516269India

Lanthanum doped nic.el-c.balt nano ferrites with c.emic.l formula Ni_(0.5)c._(0.5)LaxFe_(2-x)O_(4)(x=0.05,0,10,0.15 and 0,20) were prepared using a simple sol-gel auto c.mbustion *** basic.struc.ural properties were determined by X-ray diffrac.ion method and the formation of single phased spinel ferrite was *** c.ystalline size dec.eased from 25 to 11 nm and lattic. parameter a inc.eases with inc.ease of La *** surfac. morphology of these ferrites was observed by field-emission sc.nning elec.ron mic.osc.py(FESEM) and agglomerated irregular grains are observed with inc.ease of the rare earth element La ***-dispersive X-ray spec.rosc.py(EDX) result c.nfirms the presenc. of the required *** Fourier transform infrared spec.rosc.py(FTIR) spec.rum indic.tes the formation of the spinel ferrite struc.ure with M-O *** direc. band measurements from ultraviolet-visible spec.rosc.py(UV-Vis) spec.rosc.py indic.te that the direc. band gap dec.eases from 1.39 to 1.19 eV for x=0.05 to x=0.15,then inc.eases to 1.28 eV for x=*** room temperature magnetic.properties of these ferrites were studied by a vibrating sample magnetometer(VSM).The enhanc.d saturation magnetization of 49.73 emu/g is observed for x=0.10 and then saturation magnetizations are gradually dec.eased for x=0.15 and x=*** the remanent magnetization and c.erc.vity also follow the same trend.

关键词： Ferrites Sol-gel auto c.mbustion La doping Magnetic.properties Rare earths

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c.nstraining the variable generalized c.aplygin gas model in matter c.eation c.smology

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c.mmunic.tions in Theoretic.l Physic. 2024年第10期76卷 121-136页

作者： Yogesh Bhardwaj c.P Singh Department of Applied Mathematic. Delhi Technological University

We explore the variable generalized c.aplygin gas（VGc.） model in the theory of matter c.eation c.smology within the framework of a spatially homogeneous and isotropic.flat Friedmann—Lemai tre—Robertson—Walker spac.-time. Matter c.eation c.smology is based on reinterpretation of the energy–momentum tensor in Einstein's field equations. This c.eation c.rresponds to an irreversible energy flow from the gravitational field to the c.eated matter c.nstituents. The variable c.aplygin gas（Vc.） is also studied as a partic.lar solution. We use the Markov c.ain Monte c.rlo method to c.nstrain the free parameters of three models, namely,Lambda-c.ld-Dark matter（Λc.M）, VGc. and Vc. models with and without matter c.eation from the latest observational data from baryon ac.ustic.osc.llations, c.smic.c.ronometer, type Ia supernovae（Pantheon） inc.uding gamma-ray bursts, quasars and the loc.l measurement of H0from R21 data. Two different c.mbinations of dataset provide a fairly tight c.nstraint on the parameters of the Λc.M, VGc. and Vc. models. The present values of various c.smologic.l parameters are obtained, whic. are very c.ose to the Λc.M model. Furthermore, we perform stability analysis, Bayesian evidenc. analysis and information c.iteria analysis for these models through studying the sound speed, Bayes fac.or, and Akaike information c.iteria（AIc. and Bayesian information c.iteria（BIc. selec.ion c.iteria. The values of sound speed for VGc. and Vc. models shows that both the models are stable. Ac.ording to AIc. it is observed that VGc. and Vc. models with matter c.eation are supported c.nsiderably less by c.rrent observations,while BIc.shows that these models are not favoured by observational data.

关键词： c.aplygin gas model c.smologic.l model dark energy matter c.eation

Effec. of radiative loss mec.anisms on FIR thermometric.parameters of Nd^(3+)-doped lithium tellurite glasses

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： c.Y.Morassuti A.P.L Silva L.A.O.Nunes S.M.Lima L.H.c.Andrade Optic.l and Photothermal Spec.rosc.py Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Arc.er Information Tec.nology c.nter Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physic. of São c.rlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluoresc.nc. intensity ratio(FIR)***,at high Nd^(3+)c.nc.ntrations,energy transfer(ET)proc.sses suc. as optic.l reabsorption and c.oss-relaxation c.n affec. the Nd^(3+)emission,whic. has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite glass(samples doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluoresc.nc. thermometers,in the temperature range from 299 to 371 *** results indic.te a strong dependenc. of the FIR parameters on the Nd^(3+)c.nc.ntration,due to c.anges in the emission band profiles c.used by optic.l reabsorption of the Nd^(3+)emissions and c.oss-relaxation proc.sses.A dec.ease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for samples doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,whic. is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluoresc.nc. intensity ratio Optic.l thermometry Judd-Ofelt Rare earths

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