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Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.t.Jeong S.w.lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

the superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)w.t. a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

SMILE soft X-ray Imager flight model CCD370 pre-flight device characterisation

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Earth and Planetary Physics 2024年第1期8卷 25-38页

作者： S.Parsons D.J.Hall O.Hetherington t.w.Buggey t.Arnold M.w.J.Hubbard A.Holland Centre for Electronic Imaging the Open UniversityMilton KeynesMK76AAUK

throughout the SMILE mission the satellite will be bombarded by radiation which gradually damages the focal plane devices and degrades their *** order to understand the changes of the CCD370s w.t.in the soft X-ray Imager,an initial characterisation of the devices has been carried out to give a baseline performance *** CCDs have been characterised,the two flight devices and the flight spa *** has been carried out at the Open University in a bespo ke cleanroom measure ment *** results show.t.at there is a cluster of bright pixels in the flight spa re which increases in size w.t. tempe *** at the nominal ope rating tempe rature(-120℃) it is w.t.in the procure ment ***,the devices meet the specifications when ope rating at -120℃ in 6 × 6 binned frame transfer science *** se rial charge transfer inefficiency degrades w.t. temperature in full frame *** any charge losses are recovered when binning/frame transfer is implemented.

关键词： CCD soft X-ray imager characterisation SMILE

the CCD instrument background of the SMILE SXI

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Earth and Planetary Physics 2024年第1期8卷 15-24页

作者： M.w.J.Hubbard O.Hetherington D.J.Hall t.w.Buggey S.Parsons t.Arnold A.Holland C.Pagani S.Sembay Centre for Electronic Imaging The Open UniversityMilton KeynesMK76AAUK X-ray and Observational Astronomy Group Department of Physics&AstronomyUniversity of LeicesterLE17RHUK

the ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation *** Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is *** shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen ***,two radiation environments can be approximated based on the shutter door position:open and *** instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two *** to the correlation of the space environment w.t. the solar cycle,the solar minima and maxima,the background was also evaluated at these two *** results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar *** is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes.

关键词： instrument background X-ray astronomy space radiation

Evolution of nonmetallic inclusions in 80-t 9CrMoCoB large-scale ingots during electroslag remelting process

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1525-1539页

作者： Shengchao Duan Min Joo lee Yao Su wangzhong Mu Dong Soo Kim Joo Hyun Park School of Mechanical and Materials Engineering North China University of TechnologyBeijing 100144China Department of Materials Science and Chemical Engineering Hanyang UniversityAnsan 15588Rep.of Korea Department of Materials Science and Engineering KTH Royal Institute of TechnologyBrinellvägen 23Stockholm 10044Sweden Department of Engineering Science and Mathematics Division of Materials ScienceLuleåUniversity of Technology97187 LuleåSweden Casting&Forging Business Unit Nuclear Business GroupDoosan EnerbilityChangwon 51711Rep.of Korea

In combination w.t. theoretical calculations,experiments were conducted to investigate the evolution behavior of nonmetallic inclusions(NMIs)during the manufacture of large-scale heat-resistant steel ingots using 9CrMoCoB heat-resistant steel and CaF_(2)–CaO–Al_(2)O_(3)–SiO_(2)–B_(2)O_(3)electroslag remelting(ESR)-type slag in an 80-t industrial ESR *** main types of NMI in the consumable electrode comprised pure alumina,a multiphase oxide consisting of an Al_(2)O_(3)core and liquid CaO–Al_(2)O_(3)–SiO_(2)–MnO shell,and M_(23)C_(6)carbides w.t. an MnS *** Al_(2)O_(3)and MnS inclusions had higher precipitation temperatures than the M_(23)C_(6)-type carbide under equilibrium and nonequilibrium solidification ***,inclusions can act as nucleation sites for carbide layer *** ESR process completely removed the liquid CaO–Al_(2)O_(3)–SiO_(2)–MnO oxide and MnS inclusion w.t. a carbide shell,and only the Al_(2)O_(3)inclusions and Al_(2)O_(3)core w.t. a carbide shell occupied the remelted *** M_(23)C_(6)-type carbides in steel were determined as Cr_(23)C_(6)based on the analysis of transmission electron microscopy *** substitution of Cr w.t. w,Fe,or/and Mo in the Cr_(23)C_(6)lattice caused slight changes in the lattice parameter of the Cr_(23)C_(6)***,Cr_(21.34)Fe_(1.66)C_(6),(Cr_(19)w_(4)C_(6),Cr_(18.4)Mo_(4.6)C_(6),and Cr_(16)Fe_(5)Mo_(2)C_(6)can match the fraction pattern of Cr_(23)C_(6)*** Al_(2)O_(3)inclusions in the remelted ingot formed due to the reduction of CaO,SiO_(2),and MnO components in the liquid *** increased Al content in liquid steel or the higher supersaturation degree of Al_(2)O_(3)precipitation in the remelted ingot than that in the electrode can be attributed to the evaporation of CaF_(2)and the increase in CaO content in the ESR-type slag.

关键词： nonmetallic inclusion heat-resistant steel electroslag remelting M_(23)C_(6) carbide MnS inclusion supersaturation degree

Elevated brain temperature under severe heat exposure impairs cortical motor activity and executive function

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Journal of Sport and Health Science 2024年第2期13卷 233-244页

作者： Xiang Ren tan Mary C.Stephenson Sharifah Badriyah Alhadad Kelvin w.Z.Loh tuck wah Soong Jason K.w.lee Ivan C.C.Low Health and Social Sciences Singapore Institute of TechnologySingapore 138683Singapore Human Potential translational Research Programme Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117597Singapore Centre for translational Magnetic Resonance Research Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117549Singapore Department of Physiology Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117593Singapore Heat Resilience and Performance Centre Yong Loo Lin School of MedicineNational University of SingaporeSingapore 117510Singapore N.1 Institute for Health National University of SingaporeSingapore 117456Singapore Campus for Research Excellence and technological Enterprise(CREAtE) Singapore 138602Singapore

Background:Excessive heat exposure can lead to hyperthermia in humans,which impairs physical performance and disrupts cognitive *** heat is a known physiological stressor,it is unclear how severe heat stress affects brain physiology and ***:Eleven healthy participants were subjected to heat stress from prolonged exercise or warm w.t.r immersion until their rectal temperatures(t_(re))attained 39.5℃,inducing exertional or passive hyperthermia,*** a separate trial,blended ice was ingested before and during exercise as a cooling *** were compared to a control condition w.t. seated rest(normothermic).Brain temperature(t_(br)),cerebral perfusion,and task-based brain activity were assessed using magnetic resonance imaging ***:t_(br)in motor cortex was found to be tightly regulated at rest(37.3℃±0.4℃(mean±SD))despite fluctuations in t_(re).w.t. the development of hyperthermia,t_(br)increases and dovetails w.t. the rising t_(re).Bilateral motor cortical activity was suppressed during high-intensity plantarflexion tasks,implying a reduced central motor drive in hyperthermic participants(t_(re)=38.5℃±0.1℃).Global gray matter perfusion and regional perfusion in sensorimotor cortex were reduced w.t. passive *** function was poorer under a passive hyperthermic state,and this could relate to compromised visual processing as indicated by the reduced activation of left lateral-occipital ***,ingestion of blended ice before and during exercise alleviated the rise in both t_(re)and t_(bc)and mitigated heat-related neural ***:Severe heat exposure elevates t_(br),disrupts motor cortical activity and executive function,and this can lead to impairment of physical and cognitive performance.

关键词： Brain functional activity Cognition Heat stress Hyperthermia Motor function

Satellite-enabled enviromics to enhance crop improvement

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Molecular Plant 2024年第6期17卷 848-866页

作者： Rafael t.Resende lee Hickey Cibele H.Amaral Lucas L.Peixoto Gustavo E.Marcatti Yunbi Xu Universidade Federal de Goia´s(UFG) Agronomy DepartmentPlant Breeding SectorGoiania(GO)74690-900Brazil theCROP a Precision-Breeding Startup:EnviromicsPhenomicsand GenomicsNo Zip-codeOperating VirtuallyGoiania(GO)and Sete Lagoas(MG)Brazil Queensland Alliance for Agriculture and Food Innovation The University of QueenslandBrisbaneQLDAustralia Earth Lab Cooperative Institute for Research in Environmental SciencesUniversity of Colorado BoulderBoulderCO 80303USA Environmental Data Science Innovation&Inclusion Lab Cooperative Institute for Research in Environmental SciencesUniversity of Colorado BoulderBoulderCO 80303USA Universidade Federal de Sa˜o Joa˜o del-Rei Forest Engineering DepartmentCampus Sete LagoasSete Lagoas(MG)35701-970Brazil Institute of Crop Sciences Chinese Academy of Agricultural SciencesBeijing 100081China Peking University Institute of Advanced Agricultural Sciences WeifangShandong 261325China BGI Bioverse Shenzhen 518083China

Enviromics refers to the characterization of micro-and macroenvironments based on large-scale environmental *** providing genotypic recommendations w.t. predictive extrapolation at a site-specific level,enviromics could inform plant breeding decisions across varying conditions and anticipate productivity in a changing ***-based integration of statistics,envirotyping(i.e.,determining environmental factors),and remote sensing could help unravel the complex interplay of genetics,environment,and *** support this goal,exhaustive envirotyping to generate precise environmental profiles would significantly improve predictions of genotype performance and genetic gain in ***,informatics management platforms aggregate diverse environmental datasets obtained using optical,thermal,radar,and light detection and ranging(LiDAR)sensors that capture detailed information about vegetation,surface structure,and *** wealth of information,coupled w.t. freely available climate data,fuels innovative enviromics *** enviromics holds immense potential for breeding,a few obstacles remain,such as the need for(1)integrative methodologies to systematically collect field data to scale and expand observations across the landscape w.t. satellite data;(2)state-of-the-art AI models for data integration,simulation,and prediction;(3)cyberinfrastructure for processing big data across scales and providing seamless interfaces to deliver forecasts to stakeholders;and(4)collaboration and data sharing among farmers,breeders,physiologists,geoinformatics experts,and programmers across research *** these challenges is essential for leveraging the full potential of big data captured by satellites to transform 21st century agriculture and crop improvement through enviromics.

关键词： envirotyping precision breeding genotype-environment interactions remote sensing predictive models enviromic information

Efficient guiding and focusing of intense laser pulse using periodic thin slits

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Matter and Radiation at Extremes 2024年第4期9卷 29-39页

作者： L.Xu t.w.Huang K.Jiang C.N.wu H.Peng P.C.hen R.Li H.B.Zhuo C.t.Zhou Shenzhen Key Laboratory of Ultraintense Laser and Advanced Material technology Center for Intense Laser ApplicationTechnologyand College of Engineering PhysicsShenzhen Technology UniversityShenzhen 518118People’s Republic of China

Slits have been widely used in laser-plasma interactions as plasma optical components for generating high-harmonic light and controlling laser-driven particle ***,we propose and demonstrate that periodic thin slits can be regarded as a new breed of optical elements for efficient focusing and guiding of intense laser *** fundamental physics of intense laser interaction w.t. thin slits is studied,and it is revealed that relativistic effects can lead to enhanced laser focusing far beyond the pure diffractive focusing *** addition,the interaction of an intense laser pulse w.t. periodic thin slits makes it feasible to achieve multifold enhancement in both laser intensity and energy transfer efficiency compared w.t. conventional *** results provide a novel method for manipulating ultra-intense laser pulses and should be of interest for many laser-based applications.

关键词： laser pulse intense

栖息地条件对白杨与枫树林群落中高山天南星的丰富度和选定个体特征的影响

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Journal of Plant Ecology 2024年第1期17卷 33-49页

作者： tomasz wójcik Kinga Kostrakiewicz-Gierałt Department of Nature Conservation and Landscape Ecology Institute of Agricultural SciencesLand Management and Environmental ProtectionUniversity of Rzeszow35-601 RzeszowPoland Department of tourism Geography and Ecology Institute of TourismFaculty of Tourism and RecreationUniversity of Physical Education in Krakow31-571 KrakowPoland

本研究于2020至2021年在西喀尔巴阡山脉的山麓地区进行,研究了高山天南星(Arum alpinum)的物种数量和选定特征的空间-时间变异。调查分别在4个永久样地中进行(Patch Ⅰ、Ⅱ、Ⅲ、Ⅳ)。Patch Ⅰ和Patch Ⅲ位于以低矮植被为主的枫树-鹅耳... 详细信息

本研究于2020至2021年在西喀尔巴阡山脉的山麓地区进行,研究了高山天南星(Arum alpinum)的物种数量和选定特征的空间-时间变异。调查分别在4个永久样地中进行(Patch Ⅰ、Ⅱ、Ⅲ、Ⅳ)。Patch Ⅰ和Patch Ⅲ位于以低矮植被为主的枫树-鹅耳枥林(tilio cordatae-Carpinetum betuli)林地中,而Patch Ⅱ和Patch Ⅳ位于以阔叶物种为主的白杨(Populetum albae)河滩林中。调查结果表明,高山天南星最丰富种群出现在Patch Ⅰ,但Patch Ⅱ和Patch Ⅳ中也存在大量的营养体和繁殖个体。个体性状的时间变异性在Patch Ⅳ最低,其次是Patch Ⅰ和Patch Ⅱ,在Patch Ⅲ最高。所有种群中均发现叶柄长度与叶片尺寸以及有性茎长度与果序特征之间的关系显著呈正相关,这一发现证实了先前的研究。这些研究结果表明,高山天南星与特定的森林群落没有密切关联。充足的遮荫和湿润富养分的土壤对该物种有利,而干燥的土壤和过多的日照可能会限制其个体的开花与结果。

关键词：高山天南星(Arum alpinum) 枫树-鹅耳枥林河滩林开花茎果序叶片山地物种

Evaluation of a hepatic biomarker of nutritional imbalance in juvenile red drum(Sciaenops ocellatus) fed 60% soybean meal-based diets using NMR-based metabolomics

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Animal Nutrition 2024年第1期16卷 45-61页

作者： Fabio Casu Aaron M.w.t.on Justin Yost t.Gibson Gaylord Daniel w.Bearden Michael R.Denson Marine Resources Research Institute South Carolina Department of Natural Resources Bozeman Fish technology Center United States Fish and Wildlife Service Marine Biochemical Sciences Group Chemical Sciences Division National Institute of Standards and Technology Hollings Marine Laboratory

A 12-week feeding trial w.t. juvenile red drum(Sciaenops ocellatus) fed high-soybean meal(SBM) diets was conducted to investigate a putative biomarker of nutritional imbalance, N-formimino-L-glutamate(FIGLU). three fishmeal-free, 60% SBM pelleted diets(named B12, Fol, and Met, respectively) were tested to evaluate the effects on growth performance and tissue metabolite profiles of supplementation of vitamin B12(0.012 mg/kg), folate(10 mg/kg), methionine(1 g/kg) respectively, above basal supplementation levels. A fourth SBM-based diet(named B12/Fol/Met) was formulated w.t. a combination of B12, folate, and methionine to attain the above-mentioned target concentrations. A fifth 60% SBM diet(named FwS) w.t. methionine supplementation(1 g/kg above basal supplementation levels), enriched w.t. taurine, lysine and threonine as well as minerals, was also tested. this diet contained formulation targets and additives which have allowed for replacing fishmeal w.t. plant proteins in rainbow.t.out feeds. Control diets included a fishmeal-based diet(named FM), an unsupplemented basal 60% SBM diet(named SBM60), and a “natural” diet(named N) made up of equal parts of fish(cigar minnows), squid and shrimp as a positive reference for growth performance. Formulated feeds contained approximately 37% total crude protein, approximately 14% total crude lipid and were energetically balanced. Standard growth performance metrics were measured, and tissues(liver, muscle) were collected at week 12 to evaluate diet-induced metabolic changes using nuclear magnetic resonance(NMR)-based *** results show.t.at the FwS diet outperformed all other SBM diets and the FM diet under all performance metrics(Pwas not detected in fish fed the N diet but was detected in those fed the SBM diets and the FM diet. Fish fed the FwS diet and the Met diet showed lower hepatic levels of FIGLU compared w.t. the other SBM-based diets(Pting that among the different supplementatio

关键词： Aquaculture Metabolomics Nuclear magnetic resonance Red drum Soybean meal N-Formimino-L-glutamate