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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

Distinct Electrical and Mechanical Responses of a cu-10Fe composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.Y.Yue S.Y.Peng X.zhang c.n.He Y.z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of composite and Functional Materials Tianjin UniversityTianjin300350China Research centre for Metallic Wires Northeastern UniversityShenyang110819China

A cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the cu-10wt%Fe *** cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IAcS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance cu-based in-situ composites by post treatment.

关键词： cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

Plant cell wall-mediated disease resistance:current understanding and future perspectives

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Molecular Plant 2024年第5期17卷 699-724页

作者： Antonio Molina Lucıa Jorda Miguel Angel Torres Marina Martın-Dacal Diego Jose Berlanga Patricia Fernandez-calvo Elena Gomez-rubio Sonsoles Martın-Santamarıa centro de Biotecnología y Genómica de Plantas Universidad Politécnica de Madrid(UPM)-Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria(INIA/CSIC)Campus de Montegancedo UPMPozuelo de Alarcon(Madrid)Spain Departamento de Biotecnologıa-Biología Vegetal Escuela Técnica Superior de Ingenierıa AgronomicaAlimentarıa y de BiosistemasUPMMadridSpain centro de Investigaciones Biologicas Margarita Salas Consejo Superior de Investigaciones Científicas(CSIC)Ramiro de Maeztu 928040 MadridSpain Misión Biológica de Galicia Consejo Superior de Investigaciones Científicas(CSIC)Campus de Montegancedo UPMPozuelo de Alarcón(Madrid)Spain

Beyond their function as structural barriers,plant cell walls are essential elements for the adaptation of plants to environmental *** walls are dynamic structures whose composition and integrity can be altered in response to environmental challenges and developmental *** wall changes are perceived by plant sensors/receptors to trigger adaptative responses during development and upon stress *** cell wall damage caused by pathogen infection,wounding,or other stresses leads to the release of wall molecules,such as carbohydrates(glycans),that function as damage-associated molecular patterns(DAMPs).DAMPs are perceived by the extracellular ectodomains(EcDs)of pattern recognition receptors(PRRs)to activate pattern-triggered immunity(PTI)and disease ***,glycans released from the walls and extracellular layers of microorganisms interacting with plants are recognized as microbe-associated molecular patterns(MAMPs)by specific EcD-PRRs triggering PTI *** number of oligosaccharides DAMPs/MAMPs identified that are perceived by plants has increased in recent ***,the structural mechanisms underlying glycan recognition by plant PRRs remain ***,this knowledge is mainly focused on receptors of the LysM-PRR family,which are involved in the perception of various molecules,such as chitooligosaccharides from fungi and lipo-chitooligosaccharides(i.e.,nod/MYc factors from bacteria and mycorrhiza,respectively)that trigger differential physiological ***,additional families of plant PRRs have recently been implicated in oligosaccharide/polysaccharide *** include receptor kinases(RKs)with leucine-rich repeat and Malectin domains in their EcDs(LRR-MAL RKs),catharanthus roseus REcEPTOR-LIKE KInASE 1-LIKE group(crRLK1L)with Malectin-like domains in their EcDs,as well as wall-associated kinases,lectin-RKs,and *** characterization of structural basis of glycans recogniti

关键词： Arabidopsis thaliana cell wall damage-associated molecular patterns DAMPs disease resistance glycans oligosaccharides pattern-triggered immunity PTl pattern recognition receptor PRRs

construction of 2D/2D Ti_(3)c_(2)T_(x)MXene/cdS heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials Science & Technology 2024年第4期171卷 1-9页

作者： T.Y.Huang z.Yang S.Y.Yang z.H.Dai Y.J.Liu J.H.Liao G.Y.zhong z.J.Xie Y.P.Fang S.S.zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China School of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China School of chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)c_(2)T_(x)MXene/cdS heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)cdS nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of cdS *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure Heterostructure Photothermal effect Photocatalyst Hydrogen evolution

In situ digital testing method for quality assessment of soft soil improvement with polyurethane

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1732-1748页

作者： X.F.Wang c.J.Wang W.V.Yue z.J.zhang z.Q.Yue Department of civil Engineering China University of Geosciences (Beijing)BeijingChina Department of Water Science and Engineering Zhengzhou UniversityZhengzhouChina Department of Geotechnical Engineering Tongji UniversityShanghaiChina Department of civil Engineering The University of Hong KongChina

This study purposes an in situ testing method on quality assessment of soil *** drilling data includes the spatial distribution and in situ strength of untreated and treated soil along three different drillholes measured by on-site drilling monitoring *** factual drilling data can characterize the degree of soil improvement by penetration injection with permeable *** from on-site drilling monitoring shows that the linear zones represent constant drilling speeds shown in the plot of drill bit advancement *** drilling time,which indicates the spatial distributions of soil *** soil profile at the study site is composed of four layers,which includes fill,untreated silty clay,treated silty clay,and mucky *** results of soil profile are verified by the parallel site *** constant drilling speeds profile the coring-resistant strength of drilled *** comparing with the untreated silty clay,the constant drilling speeds of the treated silty clay have been decreased by 13.0-62.8%.Two drilling-speed-based indices of 61.2%and 65.6%are proposed to assess the decreased average drilling speed and the increased in situ strength of treated silty *** tests,*** compressive strength(UcS)test,have been performed with core sample to investigate and characterize in situ strength by comparing that with drilling *** show that the average predicted strengths of treated silty clay are 2.4-6.9 times higher than the average measured strength of untreated silty *** UcS-based indices of 374.5%and 344.2%verified the quality assessment(QA)results by this new in situ *** method provides a cost-effective tool for quality assessment of soil improvement by utilizing the digital drilling data.

关键词： Drilling process monitoring system Hydraulic rotary drilling process constant drilling speed Soil improvement Quality assessment

Early Phases of Star Formation: Testing chemical Tools

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Research in Astronomy and Astrophysics 2024年第1期24卷 96-118页

作者： n.c.Martinez S.Paron cOnIcET-Universidad de Buenos Aires.Instituto de Astronomía y Física del Espacio Ciudad Universitaria(C1428EGA)Ciudad Autónoma de Buenos AiresArgentina

Star-forming processes strongly influence the ISM ***,many high-quality databases are available at millimeter *** them,it is possible to carry out studies that review and deepen previous *** these studies involve large samples of sources,it is preferred to use direct tools to study the molecular *** the aim of testing these tools such as the use of the Hcn/Hnc ratio as a thermometer,and the use of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H as "chemical clocks," we present a molecular line study toward 55 sources representing massive young stellar objects at different evolutionary stages:infrared dark clouds(IRDcs),highmass protostellar objects(HMPOs),hot molecular cores(HMcs) and ultracompact H II *** found that the use of the Hcn/Hnc ratio as a universal thermometer in the ISM should be taken with care because the Hcn optical depth is a big issue that can affect the ***,this tool should be utilized only after a careful analysis of the Hcn spectrum,checking that no line,neither the main nor the hyperfine ones,presents absorption *** point out that the analysis of the emission of H^(13)cO^(+),Hc_(3)n,n_(2)H^(+) and c_(2)H could be useful to trace and distinguish regions among IRDcs,HMPOs and *** molecular line widths of these four species increase from the IRDc to the HMc stage,which can be a consequence of the gas dynamics related to the starforming processes taking place in the molecular *** results not only contribute with more statistics,acting as a probe of such chemical tools,useful to obtain information in large samples of sources,but also complement previous works through the analysis of other types of sources.

关键词： stars:formation ISM:molecules ISM:clouds

Imprints of a gravitational wave through the weak field deflection of photons

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chinese Physics c 2024年第8期48卷 240-245页

作者： Reggie c.Pantig Ali Övgün Physics Department Mapúa University658 Muralla St.IntramurosManila 1002Philippines Physics Department Eastern Mediterranean UniversityFamagusta99628 North Cyprusvia Mersin 10Turkiye

In this study,we investigate the novel phenomenon of gravitational lensing experienced by gravitational waves traveling past a Schwarzschild black hole perturbed by a specific,first-order,polar gravitational *** apply the Gauss-Bonnet theorem,finding a topological contribution to the deflection of light rays passing near the black *** demonstrate that the deflection angle can be determined by analyzing a region entirely outside the path of the light ray,leading to a calculation based solely on the parameters of the perturbing wave(Legendre polynomial order,l;frequency,σ).This approach offers a unique perspective on gravitational lensing and expands our understanding of black hole interactions with gravitational waves.

关键词： supermassive black holes gravitational waves chaos weak deflection angle Gauss-Bonnet theorem

Twenty years of population dynamics in European beech-oak forest at their rear range margin anticipate changes in its structure and composition

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Forest Ecosystems 2024年第3期11卷 358-370页

作者： álvaro rubio-cuadrado Iciar Alberdi Isabel canellas Fernando Montes Jesús Rodríguez-calcerrada Rosana López Guillermo G.Gordaliza María Valbuena-carabana nikos nanos Ramón Perea Luis Gil Departamento de dinamica y gestion forestal Instituto de Ciencias Forestales(ICIFOR-INIA)CSICCtra.La Coruna km 7.528040MadridSpain Departamento de Sistemas y Recursos naturales Escuela Tecnica Superior de Ingeniería de MontesForestal y del Medio NaturalUniversidad Politecnica de Madrid.Ciudad Universitaria s/n28040MadridSpain School of Forestry and natural Environment Aristotle University of ThessalonikiUniversity Campus54124ThessalonikiGreece

There is an increasing interest in restoring degraded forests,which occupy half of the forest *** the forms of restoration,passive restoration,which involves the elimination of degrading factors and the free evolution of natural dynamics by applying minimal or no management,is gaining *** dynamics is difficult to predict due to the influence of multiple interacting factors such as climatic and edaphic conditions,composition and abundance of species,and the successional character of these ***,we study the natural dynamics of a mixed forest located in central Spain,which maintained an open forest structure,due to intensive use,until grazing and cutting were banned in the *** most frequent woody species in this forest are Fagus sylvatica,Quercus petraea,Quercus pyrenaica,Ilex aquifolium,Sorbus aucuparia,Sorbus aria and Prunus avium,with contrasting shade and drought *** species are common in temperate European deciduous forest and are found here near their southern distribution limit,except for *** order to analyze forest dynamics and composition,three inventories were carried out in 1994,2005 and *** results show that,despite the Mediterranean influence,the natural dynamics of this forest has been mainly determined by different levels of shade *** the abandonment of grazing and cutting,*** expanded rapidly due to its lower shade tolerance,whereas after canopy closure and forest densification,shade-tolerant species gained ground,particularly ***,despite its lower drought and late-frost *** the current dynamics continue,*** will overtake the rest of the species,which will be relegated to sites with shallow soils and steep ***,all the multi-centennial beech trees,which are undergoing a rapid mortality and decline process,will disappear.

关键词： Forest succession Secondary forest Woodland Mixed forest competition Recruitment

The Effect of Water and Salt Stress on Paspalum dilatatum,a constituent of Pampas natural Grasslands

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Phyton-International Journal of Experimental Botany 2024年第8期93卷 2009-2018页

作者： claudia A.Porcelli Gerardo rubio Flavio H.Gutiérrez Boem Raul S.Lavado Departamento de Química Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresC1417DSEArgentina Instituto de Investigaciones en Biociencias Agricolas y Ambientales(InBA) Facultad de AgronomíaUniversidad de Buenos AiresBuenos AiresC1417DSEArgentina

The effects of the salt stress on plant growth are usually increased by the water *** studied the impact of both stresses in simultaneous pulses of drought and salinity on Paspalum *** forage species is native to South America,spread in grasslands in many tropical,subtropical,and temperate areas of the world,and very common in grasslands of the Flooding Pampas of *** what happens in *** compared a pot experiment,a non-stressed control against water stress for a month(midpoint between field capacity and wilting point),and two saline stresses(moderate,6 d·Sm^(−1)and strong,12 d·Sm^(−1)),also for a *** biomass(green leaf;non-leaf green material,and dry material)and roots were harvested,weighed,and analyzed for nitrogen,phosphorus,and *** biomass of all components significantly decreased when both stresses were *** plus strong saline stress reduced by half the total biomasses,compared to the *** proportion of aerial biomass/root biomass ratio as well as aerial green component/dry materials ratio tend to decrease when subjected to both *** concentration in plants was not significantly affected,but phosphorus concentration increased in aerial biomass components,from 0.10 to 0.18 mg·kg^(−1)between the extreme treatments,but did not change in *** concentration in plants increased(i.e.,in green leave sodium(na)increased from 0.27 to 2.01 mg·kg^(−1)between the extreme treatments),whereas other cations either did not change or decreased,affecting the ratios between *** performance allows us to infer that the na accumulation of *** behaves in an intermediate range,compared to very tolerant to salts or non-salt tolerant species of the Paspalum *** agreement,when salts were applied in the form of a pulse,*** tolerated higher salinity than that found by other authors for the same species,using continuous salinity.

关键词： Dallis grass salinity drought sodium in plants phosphorus in plants potassium/sodium ratio