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China Foundry 2024年第3期21卷 205-212页

作者： Guan-yu jiang Meng-wu Wu Xiao-guang Yang Hui Wang Yu-yuan Zhu Hubei Key Laboratory of Advanced Technology for Automotive Components Wuhan University of TechnologyWuhan 430070China Hubei Longzhong Laboratory Xiangyang 441000HubeiChina Wescast Industries(China)Co. Ltd.Wuhan 430100China

Three types of steels were designed on the basis of GX40CrNiSi25-12 austenitic heat resistant steel by adding different Mn contents(2wt.%,6wt.%,and 12wt.%).Thermodynamic calculation,microstructure characterization and mechanical property tests were conducted to investigate the effect of Mn addition on the microstructure and mechanical properties of the austenitic heat resistant *** show that the matrix structure in all the three types of steels at room temperature is completely *** NbC and M_(23)C_(6)precipitate at grain boundaries of austenite *** the increase of Mn content,the number of carbides increases and their distribution becomes more *** the Mn content increases from 1.99%to 12.06%,the ultimate tensile strength,yield strength and elongation increase by 14.6%,8.0%and 46.3%,*** improvement of the mechanical properties of austenitic steels can be explained by utilizing classic theories of alloy strengthening,including solid solution strengthening,precipitation strengthening,and grain *** increase in alloy strength can be attributed to solid solution strengthening and precipitation strengthening caused by the addition of *** improvement of the plasticity of austenitic steels can be explained from two aspects:grain refinement and homogenization of precipitated phases.

关键词： austenitic heat resistant steel manganese microstructure mechanical properties

X-Ray Source Classification Using Machine Learning:A Study with EP-WXT Pathfinder LEIA

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Research in Astronomy and Astrophysics 2024年第8期24卷 175-195页

作者： Xiaoxiong Zuo Yihan Tao yuan Liu Yunfei Xu Wenda Zhang Haiwu pan Hui Sun Zhen Zhang Chenzhou Cui Weimin yuan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China National Astronomical Data Center Beijing 100101China

X-ray observations play a crucial role in time-domain *** Einstein Probe(EP),a recently launched X-ray astronomical satellite,emerges as a forefront player in the field of time-domain astronomy and high-energy *** a focus on systematic surveys in the soft X-ray band,EP aims to discover high-energy transients and monitor variable sources in the *** achieve these objectives,a quick and reliable classification of observed sources is *** this study,we developed a machine learning classifier for autonomous source classification using data from the EP-WXT Pathfinder—Lobster Eye Imager for Astronomy(LEIA)and EP-WXT *** proposed Random Forest classifier,built on selected features derived from light curves,energy spectra,and location information,achieves an accuracy of approximately 95%on EP simulation data and 98%on LEIA observational *** classifier is integrated into the LEIA data processing pipeline,serving as a tool for manual validation and rapid classification during *** paper presents an efficient method for the classification of X-ray sources based on single observations,along with implications of most effective features for the *** work facilitates rapid source classification for the EP mission and also provides valuable insights into feature selection and classification techniques for enhancing the efficiency and accuracy of X-ray source classification that can be adapted to other X-ray telescope data.

关键词： methods data analysis-X-rays binaries-stars variables general-X-rays bursts

Rice canopy temperature is affected by nitrogen fertilizer

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Journal of Integrative Agriculture 2024年第3期23卷 824-835页

作者： Min jiang Zhang Chen yuan Li Xiaomin Huang Lifen Huang Zhongyang Huo jiangsu Key Laboratory of Crop Genetics and Physiology/jiangsu Key Laboratory of Crop Cultivation and Physiology/Agricultural College Yangzhou UniversityYangzhou 225009China jiangsu Co-lnnovation Center for Modern Production Technology of Grain Crops Yangzhou UniversityYangzhou 225009China

Canopy temperature strongly influences crop yield formation and is closely related to plant physiological ***, the effects of nitrogen treatment on canopy temperature and rice growth have yet to be comprehensively examined. We conducted a two-year field experiment with three rice varieties(HD-5, NJ-9108, and YJ-805) and three nitrogen treatments(zero-N control(CK), 200 kg ha~(–1)(MN), and 300 kg ha~(–1)(HN)). We measured canopy temperature using a drone equipped with a high-precision camera at the six stages of the growth period. Generally,canopy temperature was significantly higher for CK than for MN and HN during the tillering, jointing, booting, and heading stages. The temperature was not significantly different among the nitrogen treatments between the milky and waxy stages. The canopy temperature of different rice varieties was found to follow the order: HD-5>NJ-9108>YJ-805, but the difference was not significant. The canopy temperature of rice was mainly related to plant traits, such as shoot fresh weight(correlation coefficient r=–0.895), plant water content(–0.912), net photosynthesis(–0.84), stomatal conductance(–0.91), transpiration rate(–0.90), and leaf stomatal area(–0.83). A structural equation model(SEM) showed that nitrogen fertilizer was an important factor affecting the rice canopy *** study revealed:(1) A suite of plant traits was associated with the nitrogen effects on canopy temperature,(2) the heading stage was the best time to observe rice canopy temperature, and(3) at that stage, canopy temperature was negatively correlated with rice yield, panicle number, and grain number per panicle. This study suggests that canopy temperature can be a convenient and accurate indicator of rice growth and yield prediction.

关键词： canopy temperature rice physiological and biochemical characteristics yield

An Algorithm for Short-Circuit Current Interval in Distribution Networks with Inverter Type Distributed Generation Based on Affine Arithmetic

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Energy Engineering 2024年第7期121卷 1903-1920页

作者： Yan Zhang Bowen Du Benren pan GuannanWang Guoqiang Xie Tong jiang Electric Power Research Institute State Grid Jiangxi Electric Power Co.Ltd.Nanchang330096China School of Electrical and Electronic Engineering North China Electric Power UniversityBeijing102206China

During faults in a distribution network,the output power of a distributed generation(DG)may be ***,the output currents of distributed power sources are also affected by the output power,resulting in uncertainties in the calculation of the short-circuit current at the time of a ***,the impacts of such uncertainties around short-circuit currents will increase with the increase of distributed power ***,it is very important to develop a method for calculating the short-circuit current while considering the uncertainties in a distribution *** this study,an affine arithmetic algorithm for calculating short-circuit current intervals in distribution networks with distributed power sources while considering power fluctuations is *** proposed algorithm includes two *** the first stage,normal operations are considered to establish a conservative interval affine optimization model of injection currents in distributed power *** by the fluctuation range of distributed generation power at the moment of fault occurrence,the model can then be used to solve for the fluctuation range of injected current amplitudes in distributed power *** second stage is implemented after a malfunction *** this stage,an affine optimization model is first *** model is developed to characterizes the short-circuit current interval of a transmission line,and is constrained by the fluctuation range of the injected current amplitude of DG during normal ***,the range of the short-circuit current amplitudes of distribution network lines after a short-circuit fault occurs is *** algorithm proposed in this article obtains an interval range containing accurate results through interval *** with traditional point value calculation methods,interval calculation methods can provide more reliable analysis and calculation *** range of short-circuit current amplitude ob

关键词： Short circuit calculation inverter type distributed power supplies affine arithmetic distribution network

An Active Deception Defense Model Based on Address Mutation and Fingerprint Camouflage

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China Communications 2024年第7期21卷 212-223页

作者： Wang Shuo Chu jiang Pei Qingqi Shao Feng yuan Shuai Zhong Xiaoge State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an 710043China State Key Laboratory of Integrated Services Networks Xidian UniversityXi’an 710071China Shaanxi Key Laboratory of Blockchain and Secure Computing Xidian UniversityXi’an 710071China

The static and predictable characteristics of cyber systems give attackers an asymmetric advantage in gathering useful information and launching *** reverse this asymmetric advantage,a new defense idea,called Moving Target Defense(MTD),has been proposed to provide additional selectable measures to complement traditional ***,MTD is unable to defeat the sophisticated attacker with fingerprint tracking *** overcome this limitation,we go one step beyond and show that the combination of MTD and Deception-based Cyber Defense(DCD)can achieve higher performance than either of *** particular,we first introduce and formalize a novel attacker model named Scan and Foothold Attack(SFA)based on cyber kill ***,we develop probabilistic models for SFA defenses to provide a deeper analysis of the theoretical effect under different defense *** models quantify attack success probability and the probability that the attacker will be deceived under various conditions,such as the size of address space,and the number of hosts,attack analysis ***,the experimental results show that the actual defense effect of each strategy almost perfectly follows its probabilistic ***,the defense strategy of combining address mutation and fingerprint camouflage can achieve a better defense effect than the single address mutation.

关键词： address mutation deception defense fingerprint camouflage moving target defense probabilistic model

Recycling of waste aluminum scraps to fabricate sulfidated zero-valent iron-aluminum particles for enhanced chromate removal

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Journal of Environmental Sciences 2024年第4期138卷 650-659页

作者： Yahui Zhang Liguo Zhang Jiajia Zeng Shuqun Xu Jianyu pan Wenzhuo Huang Jianliang Sun Feng jiang Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of Environment School of EnvironmentSouth China Normal UniversityGuangzhou 510006China Guangdong Provincial Key Lab of Environmental Pollution Control and Remediation Technology School of Environmental Science&EngineeringSun Yat-Sen UniversityGuangzhou 510275China

Massive waste aluminum scraps produced from the spent aluminum products have high electron capacity and can be recycled as an attractive alternative to materials based on zerovalent iron(Fe^(0))for the removal of oxidative contaminants from *** study thus proposed an approach to fabricate micron-sized sulfidated zero-valent iron-aluminum particles(S-Al^(0)@Fe^(0))with high reactivity,electron selectivity and capacity using recycled waste aluminum scraps.S-Al^(0)@Fe^(0)with a three-layer structure contained zero-valent aluminum(Al^(0))core,Fe^(0) middle layer and iron sulfide(FeS)*** rates of chromate(Cr(Ⅵ))removal by S-Al^(0)@Fe^(0)at pH 5.0-9.0 were 1.6-5.9 times greater than that by sulfidated zero-valent iron(S-Fe^(0)).The Cr(Ⅵ)removal capacity of S-Al^(0)@Fe^(0)was 8.2-,11.3-and 46.9-fold greater than those of S-Fe0,zero-valent iron-aluminum(Al^(0)-Fe^(0))and Fe^(0),*** chemical cost of S-Al^(0)@Fe^(0) for the equivalent Cr(Ⅵ)removal was 78.5%lower than that of S-Fe^(0).Negligible release of soluble aluminum during the Cr(Ⅵ)removal was *** significant enhancement in the reactivity and capacity of S-Al^(0)@Fe^(0)was partially ascribed to the higher reactivity and electron density of the Al0core than Fe^(0).More importantly,S-Al^(0)@Fe^(0) served as an electric cell to harness the persistent and selective electron transfer from the Al^(0)-Fe^(0) core to Cr(Ⅵ)at the surface via coupling Fe^(0)-Fe^(2+)-Fe^(3+)redox cycles,resulting in a higher electron utilization ***,S-Al^(0)@Fe^(0) fabricated using recycled waste aluminum scraps can be a cost-effective and environmentally-friendly alternative to S-Fe^(0) for the enhanced removal of oxidative contaminants in industrial wastewater.

关键词： Recycled waste aluminum scraps Oxidative contaminants Cr(Ⅵ)reduction Sulfidated Al^(0)@Fe^(0)particle Electron transfer

Performance of composite foundations with different load transfer platforms and substratum stiffness over silty clay

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Journal of Mountain Science 2024年第5期21卷 1761-1774页

作者： ZHANG Shuming LIU Yan yuan Shengyang LIU Xianfeng jiang Guanlu LIU Junyan School of Civil Engineering and Architecture University of JinanJinan 250022China The Engineering Technology Research Center for Urban Underground Engineering Supporting and Risk Monitoring of Shandong Province Jinan 250022China School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of High-speed Railway Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

The semi-rigid pile-supported composite foundation is widely used in highway projects due to its effectiveness in increasing the bearing capacity and stability of *** is crucial to understand the stress distribution across the embankment width and the behaviour of unreinforced ***,five centrifuge tests were conducted to examine the bearing and deformation behaviours of NPRS(Non-Connected Piled Raft Systems)and GRPS(GeosyntheticReinforced Pile-Supported systems)with varying substratum stiffness,then a comparative analysis was conducted on embankment settlement,pressures underneath the embankments,and axial forces along the *** results indicated that greater substratum stiffness correlates with reduced settlement and deformation at various *** occurring 5 meters from the embankment toe includes settlement in NPRS and upward movement in *** potential sliding surface is primarily located within the embankment in NPRS,whereas it may extend through both the embankment and foundation in *** pile-soil stress ratio and efficiency in NPRS are higher than in GRPS across the *** axial force borne by end-bearing piles is significantly greater than that by floating *** the buried depth increases,the axial force in GRPS initially rises then declines,whereas in NPRS,it remains relatively constant within a certain range before *** study aids in assessing the applicability of composite foundations in complex railway environments and provides a reference for procedural measures under similar conditions.

关键词： Centrifuge modelling Composite foundation Failure mode Load transfer platform Substratum Stiffness Silty clay

Advanced 3D ordered electrodes for PEMFC applications: From structural features and fabrication methods to the controllable design of catalyst layers

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Green Energy & Environment 2024年第9期9卷 1336-1365页

作者： Kaili Wang Tingting Zhou Zhen Cao Zhimin yuan Hongyan He Maohong Fan Zaiyong jiang School of Chemistry & Chemical Engineering and Environmental Engineering Weifang University Beijing Key Laboratory of Ionic Liquids Clean Process State Key Laboratory of Multiphase Complex Systems CAS Key Laboratory of Green Process and Engineering Institute of Process Engineering Chinese Academy of Sciences College Engineering and Physical Sciences and School of Energy Resources University of Wyoming

The catalyst layers(CLs) electrode is the key component of the membrane electrode assembly(MEA) in proton exchange membrane fuel cells(PEMFCs). Conventional electrodes for PEMFCs are composed of carbon-supported, ionomer, and Pt nanoparticles, all immersed together and sprayed with a micron-level thickness of CLs. They have a performance trade-off where increasing the Pt loading leads to higher performance of abundant triple-phase boundary areas but increases the electrode cost. Major challenges must be overcome before realizing its wide commercialization. Literature research revealed that it is impossible to achieve performance and durability targets with only high-performance catalysts, so the controllable design of CLs architecture in MEAs for PEMFCs must now be the top priority to meet industry goals. From this perspective, a 3D ordered electrode circumvents this issue with a support-free architecture and ultrathin thickness while reducing noble metal Pt loadings. Herein, we discuss the motivation in-depth and summarize the necessary CLs structural features for designing ultralow Pt loading electrodes. Critical issues that remain in progress for 3D ordered CLs must be studied and characterized. Furthermore, approaches for 3D ordered CLs architecture electrode development, involving material design, structure optimization, preparation technology, and characterization techniques, are summarized and are expected to be next-generation CLs for PEMFCs. Finally, the review concludes with perspectives on possible research directions of CL architecture to address the significant challenges in the future.

关键词： PEMFC 3D ordered electrode Structural features Preparation technology Ultralow Pt loading

Critical Role of Ethylene-Propylene Block Copolymer in Impact Polypropylene Copolymer

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Chinese Journal of Polymer Science 2024年第3期42卷 344-351,I0007页

作者： Yu-Hui Tang Na Zhang Wei Bao Wei jiang yuan Lin Zhao-Hui Su State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Ethylene-propylene block copolymer(EbP) is a vital component in impact polypropylene copolymer(IPC), yet its distribution in the multiphase composite material and how it influences the phase structure and the mechanical properties are not well understood. In this work,four IPCs were investigated by atomic force microscopy-infrared(AFM-IR) to assess the phase compositions in situ, based on which in conjunction with the chain microstructure information obtained ex situ the distributions of the copolymer components were derived for each alloy. For the IPCs whose EbP comprises long P and long E segments, the EbP fraction was found to phase separate from the rubber and the PP matrix to form the cores of the disperse particles with the E-P segmented copolymer(EsP). In contrast, in the IPC with EbP composed of long P and short E segments, the EbP fraction formed an outer shell for the rubber particles with the cores comprising the EsP alone, and this IPC, containing a lower E comonomer content than its counterpart, exhibited both better impact resistance and higher flexural modulus. These results clarify how the chain structure of EbP governs the phase morphology in IPC, which in turn impacts the properties of the composite material.

关键词： Impact polypropylene copolymers AFM-IR Ethylene-propylene block copolymers Core-shell rubber particles

A mini review on the separation of Al,Fe and Ti elements from coal fly ash leachate

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International Journal of Coal Science & Technology 2024年第2期11卷 1-15页

作者： yuan Shi Fengqi jiang Rongjiao Wang Sasha Yang Xiaofeng Zhu Yingying Shen State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals School of Material Science and EngineeringLanzhou University of TechnologyLanzhou 730050China Department of Chemical and Biological Engineering Monash UniversityWellington RoadClaytonMelbourneVIC 3800Australia

The electricity demand is increasing rapidly with the development of society and ***-fired thermal power plants have become one of the primary sources of electricity generation for ***,coal-fired thermal power plants produce a great amount of by-product coal fly ash every *** fly ash disposal in landfills requires a sizable space and has negative environmental ***,it is crucial to develop new technologies and methods to utilize this enormous volume of solid waste in order to protect the *** this review,the fundamental physical and chemical character-istics of coal fly ash are introduced,and afterward the disposal policies and utilization ways of coal fly ash are discussed to gain a comprehensive understanding of the various ways this *** leaching of valuable metals in coal fly ash and the extraction of metal elements in leachate under different conditions are also ***,the possibility of coal fly ash to serve as a supplementary source for mineral resources is analyzed,providing a basis for its extensive use as a raw material in the metal industry in China and worldwide.

关键词： Coal fly ash Waste utilization Metals extraction