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Acta Metallurgica Sinica(english Letters) 2024年第2期37卷 308-324页

作者： Gang Niu Rui Yuan R.D.k.Misra Na Gong Zhi-Hui Zhang Hao-Xiu Chen Hui-Bin Wu Cheng-Jia Shang Xin-Ping Mao Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing100083China Laboratory for excellence in Advanced Steel Research Department of MetallurgicalMaterials and Biomedical EngineeringUniversity of Texas at El PasoEl PasoTX79968USA Institute of Materials Research and engineering Agency for ScienceTechnologyand ResearchSingapore138634Singapore Department of Materials Science and engineering University of TorontoTorontoONM5S 3E4Canada

The corrosion behavior and mechanism of 3Ni weathering steel in a simulated oceanic atmospheric environment are investigated in order to comprehend the impacts of La,as determined through electrochemical analysis and rust layer *** results of this study demonstrate that the addition of La enhances the corrosion resistance of 3Ni weathering steel in the marine atmospheric environment,thereby reducing the corrosion rate and improving the protection of the rust *** influence of La on corrosion resistance can be attributed to two primary ***,La functions as a grain refiner,minimizing the potential difference of the micro-regions on the substrate surface,thereby significantly reducing the corrosion of bare steel in the marine ***,La inhibits the process of Fe_(3)O_(4) oxidation back toγ-FeOOH during corrosion at the local site,thus decreasing the formation ofγ-FeOOH and enhancing the charge transfer *** research work may serve as a reference for expanding the application of rare earth elements in the field of weathering steel.

关键词： Weathering steel Rare earth Rust layer Corrosion behavior Corrosion resistance

Feeding ecology and interactions with mammal hosts in a symbiotic genus of birds(Buphagus spp.)in Namibia

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Avian Research 2024年第3期15卷 336-344页

作者： Michael S.Lukubwe Daniel Velarde-Garcéz Fernando Sequeira Susana Lopes Adrian J.F.k.Craig Vanessa A.Mata Department of Zoology and entomology Rhodes UniversityMakhandaSouth Africa Department of Wildlife Management and Tourism Studies University of NamibiaKatima Mulilo CampusNamibia Departamento de Biologia Faculdade de CiênciasUniversidade do PortoPortoPortugal CIBIO Centro de Investigação em Biodiversidade e Recursos GenéticosInBIO Laboratório AssociadoCampus de VairãoVairãoPortugal BIOPOLIS Program in Genomics Biodiversity and Land PlanningCIBIOCampus de VairãoVairãoPortugal

As the sole obligate symbiotic birds in Africa,oxpeckers offer a unique model for studying symbiotic *** to the multitrophic level they occupy and the context dependent foraging behavior they exhibit,the type of symbiotic relationship can be *** addition to providing a cleaning service to the host by removing ticks,oxpeckers frequently feed on blood,mucus,and saliva,inflicting potential damage on the ***,we used DNA metabarcoding on faecal samples to analyze the taxonomic composition of the trophic interactions of the Yellow-billed Oxpecker(Buphagus africanus)and Red-billed Oxpecker(***)in northeastern *** contrast to conventional methods,DNA metabarcoding allows for a detailed identification of dietary resources encompassing both mammal hosts and consumed arthropods within the same *** this information,we examined differences in the diet composition between oxpecker species and localities,as well as the co-occurrence between host and arthropod *** findings revealed that oxpeckers predominantly source their diet from mammals,ticks,and flies;however,ticks and flies rarely co-occur in the diet of an *** observed variability among individuals in their feeding ecology,which is strongly correlated with locality and,to a lesser extent,with the mammal *** noted a high degree of mobility between hosts within relatively short periods,with 32%of the samples showing traces of at least two mammal *** study illustrates the dynamic foraging behavior of these specialized symbiotic birds,shedding light on their potential role in pest control services and disease transmission.

关键词： Commensalism Diet DNA metabarcoding Oxpeckers Parasitism Trophic ecology

Verification and Validation of High-Resolution Inviscid and Viscous Conical Nozzle Flows

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Communications on Applied Mathematics and Computation 2024年第1期6卷 533-549页

作者： Luciano k.Araki Rafael B.de R.Borges Nicholas Dicati P.da Silva Chi-Wang Shu Department of Mechanical engineering Federal University of ParanáCuritiba81531-980ParanáBrazil Mathematics and Statistics Institute Rio de Janeiro State UniversityRio de Janeiro20550-900Rio de JaneiroBrazil Department of Mechanical engineering State University of MaringáMaringá87020-900ParanáBrazil Division of Applied Mathematics Brown UniversityProvidenceRI02912USA

Capturing elaborated flow structures and phenomena is required for well-solved numerical *** finite difference methods allow simple discretization of mesh and model ***,they need simpler meshes,e.g.,*** inverse Lax-Wendroff(ILW)procedure can handle complex geometries for rectangular ***-resolution and high-order methods can capture elaborated flow structures and *** also have strong mathematical and physical backgrounds,such as positivity-preserving,jump conditions,and wave propagation *** perceive an effort toward direct numerical simulation,for instance,regarding weighted essentially non-oscillatory(WeNO)***,we propose to solve a challenging engineering application without turbulence *** aim to verify and validate recent high-resolution and high-order *** check the solver accuracy,we solved vortex and Couette ***,we solved inviscid and viscous nozzle flows for a conical *** employed the finite difference method,positivity-preserving Lax-Friedrichs splitting,high-resolution viscous terms discretization,fifth-order multi-resolution WeNO,ILW,and third-order strong stability preserving *** showed the solver is high-order and captured elaborated flow structures and *** can see oblique shocks in both nozzle *** the viscous flow,we also captured a free-shock separation,recirculation,entrainment region,Mach disk,and the diamond-shaped pattern of nozzle flows.

关键词： High-resolution Compressible Navier-Stokes Free-shock separation Nozzle flow

Comparative impact behaviours of ultra high performance concrete columns reinforced with polypropylene vs steel fibres

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Defence Technology（防务技术） 2024年第10期40卷 138-153页

作者： Thong M.Pham Harrison Hyde Maw k.kaung Yan Zhuge Duong T.Tran Des Vlietstra Tung M.Tran UniSA STEMUniversity of South AustraliaMawson LakesSA 5095Australia BG&e Pty Ltd Wellington StreetPerthWA6000Australia Austral Construction Pty Ltd St Georges TerracePerthWA6000Australia Centre for Infrastructural Monitoring and Protection(CIMP) Curtin UniversityKent StBentleyWA 6102Australia Barchip Australia Pty Ltd U 26 Qualtroughq StreetWoolloongabbaQueensland4102Australia Sustainable Developments in Civil engineering Research Group Faculty of Civil EngineeringTon Duc Thang UniversityHo Chi Minh City72915Viet Nam

Polypropylene(PP) fibres have primarily used to control shrinkage cracks or mitigate explosive spalling in concrete structures exposed to fire or subjected to impact/blast loads, with limited investigations on capacity improvement. This study unveils the possibility of using PP micro-fibres to improve the impact behaviour of fibre-reinforced ultra-high-performance concrete(FRUHPC) columns. Results show that the addition of fibres significantly improves the impact behaviour of FRUHPC columns by shifting the failure mechanism from brittle shear to favourable flexural failure. The addition of steel or PP fibres affected the impact responses differently. Steel fibres considerably increased the peak impact force(up to 18%) while PP micro-fibres slightly increased the peak(3%-4%). FRUHPC significantly reduced the maximum midheight displacement by up to 30%(under 20°impact) and substantially improved the displacement recovery by up to 100%(under 20° impact). FRUHPC with steel fibres significantly improved the energy absorption while those with PP micro-fibres reduced the energy absorption, which is different from the effect of PP-macro fibre reported in the literature. The optimal fibre content for micro-PP fibres is 1% due to its minimal fibre usage and low peak and residual displacement. This study highlights the potential of FRUHPC as a promising material for impact-resistant structures by creating a more favourable flexural failure mechanism, enhancing ductility and toughness under impact loading, and advancing the understanding of the role of fibres in structural performance.

关键词： Ultra high-performance concrete Steel fibre Polypropylene micro-fibre Fibre volume fraction Impact loading Pendulum tests Columns

Macroscopic Traversable Wormholes: Minimum Requirements

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International Journal of Astronomy and Astrophysics 2024年第3期14卷 230-243页

作者： Peter k. F. kuhfittig Department of Mathematics Milwaukee School of Engineering Milwaukee USA

While wormholes are just as good a prediction of einstein’s theory as black holes, they are subject to severe restrictions from quantum field theory. To allow for the possibility of interstellar travel, a macroscopic wormhole would need to maintain sufficiently low radial tidal forces. It is proposed in this paper that the assumption of zero tidal forces, i.e., the limiting case, is sufficient for overcoming the restrictions from quantum field theory. The feasibility of this approach is subsequently discussed by 1) introducing the additional conditions needed to ensure that the radial tidal forces can indeed be sufficiently low and 2) by viewing traversable wormholes as emergent phenomena, thereby increasing the likelihood of their existence.

关键词： Morris-Thorne Wormholes Traversability Minimum Requirements Stability Compatibility with Quantum Field Theory

Scalable parallel ultrafast optical random bit generation based on a single chaotic microcomb

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Light(Science & Applications) 2024年第4期13卷 637-644页

作者： Pu Li Qizhi Li Wenye Tang Weiqiang Wang Wenfu Zhang Brent eLittle Sai Tek Chu kAlan Shore Yuwen Qin Yuncai Wang Institute of Advanced Photonics Technology School of Information EngineeringGuangdong University of TechnologyGuangzhou 51006China. key Laboratory of Photonic Technology for Integrated Sensing and Communication Ministry of Education of ChinaGuangdong University of TechnologyGuangzhou 51006China. Guangdong Provincial key Laboratory of Information Photonics Technology Guangdong University of TechnologyGuangzhou 51006China. key Laboratory of Advanced Transducers andIntelligent Control System Ministry of EducationTaiyuan University of TechnologyTaiyuan 030024China. State key Laboratory of Transient Optics and Photonics Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an 710119China. Department of Physics and Materials Science City University of Hong KongHong KongChina. School of electronic engineering Bangor UniversityBangorWales LL571UTUK

Random bit generators are critical for information security,cryptography,stochastic modeling,and *** and scalability are key challenges faced by current physical random bit ***,we propose a massively parallel scheme for ultrafast random bit generation towards rates of order 100 terabit per second based on a single micro-ring resonator.A modulation-instability-driven chaotic comb in a micro-ring resonator enables the simultaneous generation of hundreds of independent and unbiased random bit streams.A proof-of-concept experiment demonstrates that using our method,random bit streams beyond 2 terabit per second can be successfully generated with only 7 comb *** bit rate can be easily enhanced by further increasing the number of comb lines *** approach provides a chip-scale solution to random bit generation for secure communication and high-performance computation,and offers superhigh speed and large scalability.

关键词： resonator random chaotic

The proximity between hydroxyl and single atom determines the catalytic reactivity of Rh1/CeO_(2) single-atom catalysts

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Nano Research 2024年第1期17卷 397-406页

作者： Danfeng Wu Shuyun Zhou Congcong Du Juan Li Jianyu Huang Hong-xia Shen Abhaya k.Datye Shan Jiang Jeffrey T.Miller Sen Lin Haifeng Xiong State key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China State key Laboratory of Photocatalysis on energy and environment College of ChemistryFuzhou UniversityFuzhou 350002China Clean Nano energy Center State Key Laboratory of Metastable Materials Science and TechnologyYanshan UniversityQinhuangdao 066004China College of Biology and Chemical engineering Jiaxing UniversityJiaxing 314000China Department of Chemical&Biological engineering University of New MexicoAlbuquerqueNM 8731-0001USA Davidson School of Chemical engineering Purdue UniversityWest LafayetteIN 47907-2100USA Innovation Laboratory for Sciences and Technologies of energy Materials of Fujian Province(IkkeM) Xiamen 361102China Fujian key Laboratory of Rare-earth Functional Materials Fujian Shanhai Collaborative Innovation Center of Rare-earth Functional MaterialsLongyan 366300China

The local structure of the metal single-atom site is closely related to the catalytic activity of metal single-atom catalysts(SACs).However,constructing SACs with homogeneous metal active sites is a challenge due to the surface heterogeneity of the conventional ***,we prepared two Rh1/CeO_(2)SACs(0.5Rh1/r-CeO_(2)and 0.5Rh1/c-CeO_(2),respectively)using two shaped CeO_(2)(rod and cube)exposing different facets,i.e.,CeO_(2)(111)and CeO_(2)(100).In CO oxidation reaction,the T100 of 0.5Rh1/r-CeO_(2)SACs is 120°C,while the T100 of 0.5Rh1/c-CeO_(2)SACs is as high as 200°*** in-situ CO diffuse reflectance infrared Fourier transform spectroscopy(CO-DRIFTS),we found that the proximity between OH group and Rh single atom on the plane surface plays an important role in the catalytic activity of Rh1/CeO_(2)SAC system in CO *** Rh single atom trapped at the CeO_(2)(111)crystal surface forms the Rh1(OH)adjacent species,which is not found on the CeO_(2)(100)crystal surface at room ***,during CO oxidation,the OH group far from Rh single atom on the 0.5Rh1/c-CeO_(2)disappears and forms Rh1(OH)adjacent species when the temperature is above 150°*** formation of Rh1(OH)adjacentCO intermediate in the reaction is pivotal for the excellent catalytic activity,which explains the difference in the catalytic activity of Rh single atoms on two different CeO_(2)*** formed Rh1(OH)adjacent-O-Ce structure exhibits good stability in the reducing atmosphere,maintaining the Rh atomic dispersion after CO oxidation even when pre-reduced at high temperature of 500°*** functional theory(DFT)calculations validate the unique activity and reaction path of the intermediate Rh1(OH)adjacentCO species *** work demonstrates that the proximity between metal single atom and hydroxyl can determine the formation of active intermediates to affect the catalytic performances in catalysis.

关键词： crystal plane Rh1/CeO_(2)single-atom catalyst proximity of Rh and hydroxyl coordination structure CO oxidation

In situ apatite and carbonate Lu-Hf and molybdenite Re-Os geochronology for ore deposit research:Method validation and example application to Cu-Au mineralisation

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Geoscience Frontiers 2024年第5期15卷 339-354页

作者： Alexander Simpson Stijn Glorie Martin Hand Sarah e.Gilbert Carl Spandler Marija Dmitrijeva Greg Swain Angus Nixon Jacob Mulder Carsten Münker Department of earth Sciences University of AdelaideSA 5005Australia Mineral exploration Cooperative Research Centre University of AdelaideSA 5005Australia Adelaide Microscopy University of AdelaideSA 5005Australia Fortescue Level 287Adelaide TerraceEast PerthWA 6005Australia Institute of Geology und Mineralogy University of Köln50674 KölnGermany British Geological Survey NottinghamUK

The development of laser ablation inductively coupled plasma quadrupole tandem mass spectrometry(LA-ICP-Q-MS/MS)opens new opportunities to rapidly date a variety of hydrothermal *** we present in situ Lu-Hf and Re-Os dates for hydrothermal apatite and molybdenite,*** further report the first in situ Lu-Hf dates for bastnäsite,dolomite,and siderite,and assess their potential for constraining ore deposit *** method validation,we report isotope-dilution Lu-Hf dates for apatite reference material Bamble-1(1102±5 Ma)and calcite reference material Me-1(1531±7 Ma),enabling improved accuracy on matrix-matched calibration for LA-ICP-MS/MS Lu-Hf *** new methods are applied to the Vulcan Iron-Oxide Copper-Gold(IOCG)prospect in the Olympic Cu-Au Province of South *** deposits have been difficult to accurately date,given the general lack of reliable mineral geochronometers that are cogenetic with IOCG *** apatite Lu-Hf dates and molybdenite Re-Os dates demonstrate that mineralisation at Vulcan largely occurred at ca.1.6 Ga,contemporaneous with the world class Olympic Dam *** data also indicates that the Lu-Hf system in apatite is more robust than the U-Pb system for determining the timing of primary apatite formation in an IOCG *** further demonstrate that dolomite can retain Lu-Hf growth ages over an extended time period(>1.5 billion years),providing constraints on the timing of primary ore mineral crystallisation during brecciation and IOCG ***,late Neoproterozoic(ca.589–544 Ma)and Carboniferous(ca.334±7 Ma)Lu-Hf dates were obtained for texturally late Cubearing carbonate veins,illustrating that the carbonate Lu-Hf method allows direct dating of Cu remobilisation *** has important implications for mineral exploration as the remobilised Cu may have been transferred to younger deposits hosted in Neoproterozoic sedimentary basins overlaying the Olympic IOCG provi

关键词： Reaction-cell ICP-MS In-situ geochronology Lu-Hf Re-Os Iron Oxide Copper Gold Metal fluids

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PeT/MRI改善癌症患儿管理

中华核医学与分子影像杂志 2024年第2期44卷 124-128页

作者： Lucia Baratto k.elizabeth Hawk Lisa States Jing Qi Sergios Gatidis Louise kiru Heike e.Daldrup-Link 陈素芸(译) 王辉(审校) Department of Radiology Stanford UniversityStanfordCalifornia Department of Radiology Children′s Hospital of PhiladelphiaPhiladelphiaPennsylvania Department of Radiology Children′s WisconsinMilwaukeeWisconsin Department of Diagnostic and Interventional Radiology University Hospital TübingenTübingenGermany Department of Pediatrics Stanford UniversityStanfordCalifornia 上海交通大学医学院附属新华医院核医学科上海200092

一体化PeT/MRI通过一站式成像提供肿瘤解剖学及功能评估,且与^(18)F-FDG PeT/CT相比其辐射暴露量减少80%,因此对癌症患儿的分期与再分期具有显著临床价值。该文回顾了^(18)F-FDG PeT/MRI在小儿肿瘤中的临床应用,尤其关注PeT/MRI在患儿... 详细信息

一体化PeT/MRI通过一站式成像提供肿瘤解剖学及功能评估,且与^(18)F-FDG PeT/CT相比其辐射暴露量减少80%,因此对癌症患儿的分期与再分期具有显著临床价值。该文回顾了^(18)F-FDG PeT/MRI在小儿肿瘤中的临床应用,尤其关注PeT/MRI在患儿管理中的价值。来自4个不同机构的PeT/MRI应用先行者分享了他们对PeT/MRI技术在癌症患儿评估中特殊优势的见解。文章作者讨论了全身PeT/MRI在评估某些解剖区域(如软组织和骨髓)中的价值以及儿童特殊的PeT/MRI影像学特征,并强调了全身PeT/MRI如何通过在不失去诊断准确性的同时减少所需放射学检查次数(因此减少辐射暴露),改善淋巴瘤、肉瘤和神经纤维瘤病患儿的临床管理。文章论述了PeT/MRI如何帮助区分恶性肿瘤与感染性或炎性疾病;另外,简要探讨了PeT/MRI用于接受免疫治疗的患儿疗效评估以及对不同诊疗一体化药物评估的未来研究方向。从儿童应用中所获得的经验也可拓展至成人患者的评估中。

关键词：肿瘤学儿科学 PeT/MRI 癌症儿科肿瘤学

A machine learning-based calibration method for strength simulation of self-piercing riveted joints

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Advances in Manufacturing 2024年第3期12卷 465-483页

作者： Yu-Xiang Ji Li Huang Qiu-Ren Chen Charles k.S.Moy Jing-Yi Zhang Xiao-Ya Hu Jian Wang Guo-Bi Tan Qing Liu key Laboratory for Light-weight Materials Nanjing Tech UniversityNanjing210009People’s Republic of China Design School Xi’an Jiaotong-Liverpool UniversitySuzhou215123JiangsuPeople’s Republic of China Materials Bigdata and Applications Division Materials Academy JitriSuzhou215131JiangsuPeople’s Republic of China School of Mechanical engineering Nanjing University of Science and TechnologyNanjing210094People’s Republic of China

This paper presents a new machine learning-based calibration framework for strength simulation models of self-piercing riveted(SPR)*** simulations were conducted through the integrated modeling of SPR joints from process to performance,while physical quasi-static tensile tests were performed on combinations of DP600 high-strength steel and 5754 aluminum alloy sheets under lap-shear loading conditions.A sensitivity study of the critical simulation parameters(e.g.,friction coefficient and scaling factor)was conducted using the controlled variables method and Sobol sensitivity analysis for feature ***,machine-learning-based surrogate models were used to train and accurately represent the mapping between the detailed joint profile and its load-displacement *** of the simulation model is defined as a dual-objective optimization task to minimize errors in key load displacement features between simulations and experiments.A multi-objective genetic algorithm(MOGA)was chosen for *** three combinations of SPR joints illustrated the effectiveness of the proposed framework,and good agreement was achieved between the calibrated models and experiments.

关键词： Machine learning Self-piercing riveting(SPR) Sensitivity analysis Multi-objective optimization