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Effect of radiative loss mechanisms 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 optical and Photothermal Spectroscopy Group(GEoF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of São Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite glasses are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which 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 fluorescence thermometers,in the temperature range from 299 to 371 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease 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,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite glass Fluorescence intensity ratio optical thermometry Judd-ofelt Rare earths

Numerical analysis of high‑speed railway slab tracks using calibrated and validated 3D time‑domain modelling

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Railway Engineering Science 2024年第1期32卷 36-58页

作者： A.F.Esen o.Laghrouche P.K.Woodward D.Medina‑Pineda Q.Corbisez J.y.Shih D.P.Connolly Institute for High‑Speed Rail and System Integration University of LeedsLeeds LS29JTUK Institute for Infrastructure and Environment Heriot-Watt UniversityEdinburgh EH144ASUK Alstom Transport Saint‑OuenFrance Birmingham Centre for Railway Research and Education University of BirminghamBirmingham B152TTUK

Concrete slabs are widely used in modern railways to increase the inherent resilient quality of the tracks,provide safe and smooth rides,and reduce the maintenance *** this paper,the elastic performance of a novel slab trackform for high-speed railways is investigated using three-dimensional finite element modelling in *** is then compared to the performance of a ballasted ***,slab and ballasted track models are developed to replicate the full-scale testing of track *** the models are calibrated with the experimental results,the novel slab model is developed and compared against the calibrated slab track *** slab and ballasted track models are then extended to create linear dynamic models,considering the track geodynamics,and simulating train passages at various speeds,for which the Ledsgard documented case was used to validate the *** travelling at low and high speeds are analysed to investigate the track deflections and the wave propagation in the soil,considering the issues associated with critical *** train loading methods are discussed,and the most practical approach is retained and ***,correlations are made between the geotechnical parameters of modern high-speed rail and conventional *** is found that considering the same ground condition,the slab track deflections are considerably smaller than those of the ballasted track at high speeds,while they show similar behaviour at low speeds.

关键词： High-speed railways Slab track New ballastless track Ballasted track Critical speeds Finite element modelling Calibration of numerical models

Valorization of Tree Bark-Derived Suberin in Applications for the Bio-Based Composites Industry–A Recent Review

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Journal of Renewable Materials 2024年第6期12卷 1029-1042页

作者： Aleksandra Jeżo Institute of Wood Sciences and Furniture SGGWNowoursynowska St.159Warsaw02-776Poland

Bark extracts are sustainable sources of biopolymers and hold great promise for replacing fossil fuel-based polymers,for example,in wood-based *** addition to primary and secondary metabolites,tree bark also contains suberin,which plays a major role in protecting the tree from environmental *** is a natural aliphatic-aromatic cross-linked polyester present in the cell walls of both normal and damaged external tissues,the main component of which are long-chain aliphatic *** main role as a plant ingredient is to protect against microbiological factors and water *** of the most important suberin monomers are suberin fatty acids,known for their hydrophobic and barrier ***,due to the diverse chemical composition of suberin,it is an attractive alternative to hydrocarbon-based *** its potential is recognized,it is not widely used in biocomposites technology,including wood-based composites and the polymer *** article will discuss the current knowledge about the potential of suberin and its components in biocomposites technology,which will include surface finishes,composite adhesives and polymer blends.

关键词： Suberin suberinic acids wood composites biocomposites biopolyester

Investigation of the effects of radial clearance on the screw conveyor performances for different inclinations

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Particuology 2024年第9期92卷 72-80页

作者： Berna Bolat Birgül Aşçıoğlu Temiztaş Enes Sezer Department of Mechanical Engineering Yıldız Technical University34349BeşiktaşİstanbulTurkey

Screw conveyors are widely used for bulk material *** study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination *** Discrete Element Method(DEM)is employed to analyze the effects of different radial clearances on conveyor performance for concrete aggregate and sand as bulk *** efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial clearance and inclination *** validation is conducted to corroborate the *** the study,the optimal radial clearance was identified as 1.5 to 3 times of the particle *** optimal clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.

关键词： Screw conveyors Radial clearance Discrete element method(DEM) Volumetric efficiency Conveyor performance

In-situ construction of grass-like hybrid architecture responsible for extraordinary corrosion performance: Experimental and theoretical approach

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Nano Materials Science 2024年第1期6卷 44-59页

作者： T.Suhartono F.Hazmatulhaq y.Sheng A.Chaouiki M.P.Kamil y.G.Ko Materials Electrochemistry Group School of Materials Science and EngineeringYeungnam UniversityGyeongsan38541Republic of Korea Research Center for Advanced Materials National Research and Innovation Agency(BRIN)South TangerangBanten15314Indonesia

Despite the engineering potential by the co-existence of inorganic and organic substances to protect vulnerable metallic materials from corrosive environments,both their interaction and in-situ formation mechanism to induce the nature-inspired composite remained less *** present work used three distinctive mercaptobenzazole(MB)compounds working as corrosion inhibitors,such as 2-mercaptobenzoxazole(MBo),2-mercaptobenzothiazole(MBT),and 2-mercaptobenzimidazole(MBI)in a bid to understand how the geometrical structure arising from o,S,and N atoms affected the interaction toward inorganic *** compounds that were used here to control the corrosion kinetics would be interacted readily with the pre-existing Mgo layer fabricated by plasma *** phenomenon triggered the nucleation of the root network since MB compounds were seen to be adsorbed actively on the defective surface through the active sites in MB ***,the molecule with twin donor atoms adjacent to the mercapto-sites affected the facile growth of the grass-like structures with‘uniform’distribution via molecular self-assembly,which showed better corrosion performance than those with having dissimilar donor atoms with the inhibition efficiency(η)of 97%*** formation mechanism underlying nucleation and growth behavior of MB molecule was discussed concerning the theoretical calculation of density functional theory.

关键词： Nature-inspired composite organic-inorganic interaction Corrosion inhibitor Density functional theory Electrochemistry

Impact of device resistances in the performance of graphene‑based terahertz photodetectors

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Frontiers of optoelectronics 2024年第2期17卷 87-97页

作者： o.Castelló Sofía M.López Baptista K.Watanabe T.Taniguchi E.Diez J.E.Velázquez-Pérez y.M.Meziani J.M.Caridad J.A.Delgado-Notario Department of Applied Physics University of Salamanca37008 SalamancaSpain Unidad de Excelencia en Luz y Materia Estructurada(LUMES) University of Salamanca37008 SalamancaSpain Research Center for Electronic and optical Materials National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Research Center for Materials Nanoarchitectonics National Institute for Materials Science1-1 NamikiTsukuba 305-0044Japan Nanotechnology Group USAL-NanolabUniversity of Salamanca37008 SalamancaSpain

In recent years,graphene field-effect-transistors(GFETs)have demonstrated an outstanding potential for terahertz(THz)photodetection due to their fast response and *** features are essential to enable emerging THz applications,including 6G wireless communications,quantum information,bioimaging and ***,the overall performance of these photodetectors may be utterly compromised by the impact of internal resistances presented in the device,so-called access or parasitic *** this work,we provide a detailed study of the influence of internal device resistances in the photoresponse of high-mobility dual-gate GFET *** dual-gate architectures allow us to fine tune(decrease)the internal resistance of the device by an order of magnitude and consequently demonstrate an improved responsivity and noise-equivalent-power values of the photodetector,*** results can be well understood by a series resistance model,as shown by the excellent agreement found between the experimental data and theoretical *** findings are therefore relevant to understand and improve the overall performance of existing high-mobility graphene photodetectors.

关键词： Graphene THz Photodetector Field-effect transistor Plasmonic

Effect of Al_(2)o_(3)on the Mechanical Properties of(B_(4)C+Al_(2)o_(3))/Al Neutron Absorbing Materials

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Acta Metallurgica Sinica(English Letters) 2024年第8期37卷 1411-1420页

作者： J.X.Cai B.M.Shi N.Li y.Liu Z.G.Zhang y.N.Zan Q.Z.Wang B.L.Xiao Z.y.Ma Shi‑Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Nuclear Equipment Division Beijing Institute of Nuclear EngineeringChina Nuclear Power Engineering Co.Ltd.Beijing 100840China Department of Materials Science School of Mechanical EngineeringShenyang UniversityShenyang 110044China

B_(4)C/Al composites are widely utilized as neutron absorbing materials for the storage and transportation of spent nuclear *** order to improve the high-temperature mechanical properties of B_(4)C/Al composites,in-situ nano-Al_(2)o_(3)was introduced utilizing oxide on Al powder *** this study,the Al_(2)o_(3)content was adjusted by utilizing spheroid Al powder with varying diameters,thereby investigating the impact of Al_(2)o_(3)content on the tensile properties of(B_(4)C+Al_(2)o_(3))/Al *** was found that the pinning effect of Al_(2)o_(3)on the grain boundaries could hinder the recovery of dislocations and lead to dislocation accumulation at high *** the result,with the increase in Al_(2)o_(3)content and the decrease in grain size,the high-temperature strength of the composites increased *** finest Al powder used in this investigation had a diameter of 1.4μm,whereas the resultant composite exhibited a maximum strength of 251 MPa at room temperature and 133 MPa at 350℃,surpassing that of traditional B_(4)C/Al composites.

关键词： Al matrix composites Neutron absorbing materials (B_(4)C+Al_(2)o_(3))/Al composites High-temperature strength

Comparison of Perovskite Systems Based on AFeo_(3)(A=Ce,La,y)in Co_(2) Hydrogenation to Co

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Transactions of Tianjin University 2024年第4期30卷 337-358页

作者： Anna N.Matveyeva Shamil o.omarov Laboratory of Materials and Processes for Hydrogen Energy Ioff e Institute194021 St.PetersburgRussia

Co_(2) is the most cost-eff ective and abundant carbon resource,while the reverse water-gas reaction(rWGS)is one of the most eff ective methods of Co_(2) *** work presents a comparative study of rWGS activity for perovskite systems based on AFeo_(3)(where A=Ce,La,y).These systems were synthesized by solution combustion synthesis(SCS)with diff erent ratios of fuel(glycine)and oxidizer(φ),diff erent amounts of NH 4 No_(3),and the addition of alumina or silica as *** techniques,including X-ray diff raction analysis,thermogravimetric analysis,Fourier transform infrared spectroscopy(FTIR),scanning electron microscopy,energy-dispersive X-ray spectroscopy,N 2-physisorption,H_(2) temper-ature-programmed reduction,temperature-programmed desorption of H_(2) and Co_(2),Raman spectroscopy,and in situ FTIR,were used to relate the physicochemical properties with the catalytic performance of the obtained *** specifi c perovskite-containing system(either bulk or supported)has its own optimalφand NH_(4) No_(3) amount to achieve the highest yield and dispersion of the perovskite *** all synthesized systems,bulk SCS-derived La-Fe-o systems showed the highest resistance to reducing environments and the easiest hydrogen desorption,outperforming La-Fe-o produced by solgel combustion(SGC).Co_(2) conversion into Co at 600°C for bulk ferrite systems,depending on the A-cation type and preparation method,follows the order La(SGC)yoperties between La-Fe-o obtained by the SCS and SGC methods can be attributed to diff erent ratios of oxygen and lanthanum vacancy contributions,hydroxyl coverage,morphology,and free iron oxide *** situ FTIR data revealed that Co_(2) hydrogenation occurs through formates generated under reaction conditions on the bulk system based on La-Fe-o,obtained by the SCS method.γ-Al_(2)o_(3) improves the dispersion of CeFeo_(3) and LaFeo_(3) phases,the specifi c surface area,and the quant

关键词： Perovskites LaFeo_(3) CeFeo_(3) yFeo_(3) Solution combustion synthesis Co_(2) hydrogenation Reverse water–gas reaction(rWGS)

Addressing poxvirus challenges in the Middle East to enhance biosafety and biosecurity measures

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Journal of Biosafety and Biosecurity 2024年第3期6卷 142-156页

作者： Laith N.AL-Eitan Haneen o.Ali Hana S.Abu Kharmah Maryam K.Alasmar Iliya y.Khair Ahmad H.Mihyar Department of Applied Biological Sciences Jordan University of Science and Technology22110 IrbidJordan Department of Biotechnology and Genetic Engineering Jordan University of Science and Technology22110 IrbidJordan

The emergence and zoonotic transmission of poxviruses in the Middle East have been recognized as complex public health ***,a vast family of DNA viruses,can infect many hosts,including animals and *** Middle East has had multiple epidemics of poxvirus infections(e.g.,Monkeypox,Smallpox,and Camelpox)that have raised concerns owing to their detrimental effects on livestock,wildlife,and sporadic human *** review aims to thoroughly examine the complexity of the epidemiological patterns,intricate genetic diversity,and several contributing factors that support the emergence and zoonotic transmission of poxviruses in the Middle *** aspects of poxviruses contribute to the emergence of endemics and zoonotic breakouts,such as the complex nature of human-animal interactions,environmental changes,and their subtle capacity for viral *** review was compiled in the hopes of contributing to the current understanding of poxvirus biology and its implications for human and animal health in the Middle *** provide a comprehensive overview of the most common poxviruses in the Middle East,including their classification,structure,replication cycle,pathogenesis,route of transmissions,and of how the Middle East has developed ways to mitigate these biological threats.

关键词： Pox viruses Middle East Emergence Zoonotic Transmission