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Existence of long-range magnetic order in Heisenberg spin nanoribbons with edge modification

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Communications in Theoretical Physics 2024年第7期76卷 134-144页

作者： da-cheng ma ling-yi Cui Chu-xiao Sun Xiao-dan Chi Zheng-Nan XianYu An Du College of Science Northeastern UniversityShenyang 110819China Department of Basic Science Dalian Naval AcademyDalian 116018China Department of Physics College of SciencesShenyang University of Chemical TechnologyShenyang 110142China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityChina Key Laboratory of data Analytics and Optimization for Smart Industry(Northeastern University) Ministry of EducationChina

Long-range magnetic order appears on a side decorated Heisenberg spin nanoribbon at nonzero temperature,although no spontaneous magnetization exists in a one-or two-dimensional isotropic Heisenberg model at any nonzero temperature according to the Mermin-Wagner *** use of the spin Green's function method,we calculated the magnetizations of Heisenberg nanoribbons decorated by side spins with single-ion anisotropy and found that the system exhibits a nonzero transition temperature,whether the decorated edge spins of the system link together or separate from each *** the width of the nanoribbon achieves infinite limit,the transition temperatures of the system tend to the same finite constant eventually whether one edge or both edges are decorated by side spins in the *** results reveal that the magnetism of a low-dimensional spin system is different from that of a threedimensional spin *** the single-ion anisotropy of edge spins in a Heisenberg spin nanoribbon can be modulated by an electric field experimentally,various useful long-range magnetic orders of the system can be *** work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

关键词： Nanoribbon magnetic anisotropy long-range magnetic order Heisenberg model transition temperature

Gradient microstructure and superior strength-ductility synergy of AZ61 magnesium alloy bars processed by radial forging with different deformation temperatures

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Journal of materials Science & Technology 2024年第3期170卷 65-77页

作者： Jingfeng Zou Lifeng ma Yanchun Zhu ling Qin Yuan Yuan School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Heavy machinery Engineering Research Center of the Ministry Education Taiyuan University of Science and TechnologyTaiyuan 030024China Department of Engineering University of HullCottingham RdHull HU67RXUK National Engineering Research Center for magnesium Alloys Chongqing UniversityChongqing 400044China

Gradient microstructure modification is a cost-efficient strategy for high strength without compromising ductility,which is urgently needed in the fundamental science of engineering *** this study,heterogeneous structures of AZ61 alloy bars with anisotropic gradients(with different grain size distributions from the surface to the center)were observed to exhibit strong strength-ductility synergies under different deformation tem *** results reveal that the grain refinement process under mediumlow temperature deformation conditions(≤350℃)consists of four transition stages along the radial direction,i.e.,twin activations and deformation band formations,dislocation cells and pile-ups,ultrafine sub-grains,and randomly orientated quasi-micron *** deformation temperatures have a great influence on twin activations and deformation band formations,and the high temperature can easily provoke the initiation of non-basal *** deformation bands were determined as a primary nucleation site due to their highly unstable dislocation hindrance *** in combination with the Radial forging(RF)deformation process,the differences of dynamic precipitates can be attributed to microstructural difference and solubility limit of Al at different tem *** summarizing the tensile test results,the sample forged at 350℃exhibited the best strength-ductility synergy,exhibiting the highest elongation(EL)of 23.2%with a 251 MPa yield strength(YS)and 394 MPa ultimate tensile strength(UTS)in center region,and combined with the highest strength value of 256 MPa YS and 420 MPa UTS in the center region,while the EL was slightly degraded to 19.8%.

关键词： Gradient microstructure Radial forging Strength-ductility synergy magnesium alloy Strengthening mechanism

A Survey of Knowledge Graph Construction Using machine Learning

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Computer Modeling in Engineering & Sciences 2024年第4期139卷 225-257页

作者： Zhigang Zhao Xiong Luo maojian Chen ling ma School of Computer and Communication Engineering University of Science and Technology BeijingBeijing100083China Shunde Innovation School University of Science and Technology BeijingFoshan528399China Beijing Key Laboratory of Knowledge Engineering for materials Science Beijing100083China

Knowledge graph(KG)serves as a specialized semantic network that encapsulates intricate relationships among real-world entities within a structured *** framework facilitates a transformation in information retrieval,transitioning it from mere string matching to far more sophisticated entity *** this transformative process,the advancement of artificial intelligence and intelligent information services is ***,the role ofmachine learningmethod in the construction of KG is important,and these techniques have already achieved initial *** article embarks on a comprehensive journey through the last strides in the field of KG via machine *** a profound amalgamation of cutting-edge research in machine learning,this article undertakes a systematical exploration of KG construction methods in three distinct phases:entity learning,ontology learning,and knowledge ***,a meticulous dissection of machine learningdriven algorithms is conducted,spotlighting their contributions to critical facets such as entity extraction,relation extraction,entity linking,and link ***,this article also provides an analysis of the unresolved challenges and emerging trajectories that beckon within the expansive application of machine learning-fueled,large-scale KG construction.

关键词： Knowledge graph(KG) semantic network relation extraction entity linking knowledge reasoning

Evaluation and analysis of intraspecific competition in maize: A case study on plant density experiment

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Journal of Integrative Agriculture 2018年第10期17卷 2235-2244页

作者： ZHAI Li-chao XIE Rui-zhi MING Bo LI Shao-kun ma da-ling Institute of Crop Sciences Chinese Academy of Agricultural Sciences/Key Laboratory of Crop Physiology and Ecology Ministry of Agriculture Center for Agricultural Resources Research Institute of Genetics and Development Biology Chinese Academy of Sciences Key Laboratory of Cash Crop Stress Biology for Ulanqab Jining Normal University

Intraspecific competition is a common phenomenon in agricultural production,and maize is one of the most sensitive grass species to intraspecific competition due to its low tillering *** study evaluated and analyzed intraspecific competition in maize,and screened competitive indices that could be used to evaluate intraspecific competition in a maize population.A 2-year field experiment was conducted using the maize hybrid Zhongdan 2 at 12 plant densities ranging from 1.5 to 18.0 plants（pl）*** results showed that the response of single-plant grain yield and dry matter at harvest to increased plant density decreased exponentially and that the harvest index decreased *** response of population-level grain yield to plant density was curvilinear,producing a maximum value at the optimum population ***,the yielddensity equation agreed well with the Steinhart-Hart equation curves,but not with the quadratic equation curves reported by most previous *** indices are used to evaluate competition in a plant population or plant *** present results show that competitive intensity（CI）and absolute severity of competition（ASC）increased with increasing plant density;however,relative yield（RY）and relative reproductive efficiency（RReff）*** different responses of these indices reflect different aspects of *** to the analysis of CI,ASC,RY,and RReff,higher CI and ASC values indicate higher intraspecific competition,whereas higher RY and RReff values indirectly reflect lower intraspecific *** competitive indices evaluate not only the intraspecific competitive intensity under different plant densities of the same cultivar but also those of different cultivars under the same plant ***,some overlap exists in the calculations of ASC,CI,and RY,so one could simply select any one of these indices to evaluate intraspecific competition in a maize *** conclusion,the present study

关键词： maize intraspecific competition plant density competitive indices grain yield

Robust Space-Time Adaptive Track-Before-Detect Algorithm Based on Persymmetry and Symmetric Spectrum

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Journal of Beijing Institute of Technology 2024年第1期33卷 65-74页

作者： Xiaojing Su da Xu Dongsheng Zhu Zhixun ma Institute of Acoustics Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Underwater monopulse space-time adaptive track-before-detect method,which combines space-time adaptive detector(STAD)and the track-before-detect algorithm based on dynamic programming(DP-TBD),denoted as STAD-DP-TBD,can effectively detect low-speed weak ***,due to the complexity and variability of the underwater environment,it is difficult to obtain sufficient secondary data,resulting in a serious decline in the detection and tracking performance,and leading to poor robustness of the *** this paper,based on the adaptive matched filter(AMF)test and the RAO test,underwater monopulse AMF-DP-TBD algorithm and RAO-DP-TBD algorithm which incorporate persymmetry and symmetric spectrum,denoted as PSAMF-DP-TBD and PS-RAO-DP-TBD,are proposed and compared with the AMF-DP-TBD algorithm and RAO-DP-TBD algorithm based on persymmetry array,denoted as P-AMF-DP-TBD and *** simulation results show that the four methods can work normally with sufficient secondary data and slightly insufficient secondary data,but when the secondary data is severely insufficient,the P-AMF-DP-TBD and P-RAO-DP-TBD algorithms has failed while the PSAMF-DP-TBD and PS-RAO-DP-TBD algorithms still have good detection and tracking capabilities.

关键词： space-time adaptive detection track before detect robustness persymmetric property symmetric spectrum AMF test RAO test

Regulating zinc ion transport behavior and solvated structure towards stable aqueous Zn metal batteries

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Journal of Energy Chemistry 2024年第6期93卷 609-626,I0015页

作者： Qiang ma Aoen ma Shanguang Lv Bowen Qin Yali Xu Xianxiang Zeng Wei ling Yuan Liu Xiongwei Wu College of materials Engineering Henan International Joint Laboratory of Rare Earth Composite MaterialsHenan University of EngineeringZhengzhou 451191HenanChina Nanozyme Medical Center School of Basic Medical SciencesZhengzhou UniversityZhengzhou 450001HenanChina School of Chemistry and materials Science Hunan Agricultural UniversityChangsha 410125HunanChina College of Electrical and Information Engineering Hunan UniversityChangsha 410082HunanChina Hunan Province Yin Feng New Energy Co.Ltd. Changsha 410019HunanChina

Aqueous Zn metal batteries(AZMBs)with intrinsic safety,high energy density and low cost have been regarded as promising electrochemical energy storage ***,the parasitic reaction on metallic Zn anode and the incompatibility between electrode and electrolytes lead to the deterioration of electrochemical performance of AZMBs during the *** critical point to achieve the stable cycling of AZMBs is to properly regulate the zinc ion solvated structure and transfer behavior between metallic Zn anode and *** recent years,numerous achievements have been made to resolve the formation of Zn dendrite and interface incompatible issues faced by AZMBs via optimizing the sheath structure and transport capability of zinc ions at electrode-electrolyte *** this review,the challenges for metallic Zn anode and electrode-electrolyte interface in AZMBs including dendrite formation and interface characteristics are *** the influences of different strategies involving designing advanced electrode structu re,artificial solid electrolyte interphase(SEI)on Zn anode and electrolyte engineering to regulate zinc ion solvated sheath structure and transport behavior are summarized and ***,the perspectives for the future development of design strategies for dendrite-free Zn metal anode and long lifespan AZMBs are also given.

关键词： aqueous Zn metal batteries Zn metal anode Transport behavior Solvated structure Dendrite-free

In^(3+)-doped Sr_(2)Fe_(1.5)Mo_(0.5)O_(6−δ)cathode with improved performance for an intermediate-temperature solid oxide fuel cell

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Nano Research 2024年第1期17卷 407-415页

作者： Yumei ma Lijie Zhang Kang Zhu Binze Zhang Ranran Peng Changrong Xia ling Huang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of ChemistryXinjiang UniversityUrumqi 830046China Department of materials Science and Engineering University of Science and Technology of ChinaHefei 230026China

Promoting the oxygen reduction reaction(ORR)is critical for commercialization of intermediate-temperature solid oxide fuel cells(IT-SOFCs),where Sr_(2)Fe_(1.5)Mo_(0.5)O_(6)−δ(SFM)is a promising cathode by working as a mixed ionic and electronic *** this work,doping of In^(3+)greatly increases the oxygen vacancy concentration and the content of adsorbed oxygen species in Sr_(2)Fe_(1.5)Mo_(0.5−x)InxO_(6−δ)(SFMInx),and thus effectively promotes the ORR *** a typical example,SFMIn_(0.1)reduces the polarization resistance(R_(p))from 0.089 to 0.046Ω∙cm^(2)at 800°C,which is superior to those doped with other metal *** addition,SFMIn0.1 increases the peak power density from 0.92 to 1.47 W∙cm^(−2)at 800°C with humidified H_(2)as the fuel,indicating that In3+doping at the Mo site can effectively improve the performance of SOFC cathode material.

关键词： solid oxide fuel cell cathode In3+doping oxygen reduction reaction(ORR) Sr_(2)Fe_(1.5)Mo_(0.5)O_(6-δ)

Nano-silica modified lightweight and high-toughness carbon fiber/phenolic ablator with excellent thermal insulation and ablation performance

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Defence Technology（防务技术） 2024年第1期31卷 192-199页

作者： Wenjie Xu Wenda Song Xianfeng Jia Cheng ma Jitong Wang Wenming Qiao Licheng ling State Key Laboratory of Chemical Engineering East China University of Science and TechnologyShanghai 200237China School of Chemical Engineering and materials Changzhou Institute of TechnologyChangzhou 213032China Key Laboratory of Specially Functional Polymeric materials and Related Technology(Ministry of Education) School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China

Lightweight and high-toughness carbon fiber/phenolic ablator(CFPA)is required as the Thermal Protection System(TPS)material of aerospace vehicles for next-generation space *** improve the ablative properties,silica sol with good particle size distribution prepared using tetramethoxysilane(TMOS)was blended with natural rubber latex and deposited onto carbon fiber felt,which was then integrated with phenolic aerogel matrix,introducing nano-silica into the framework of *** modified CFPA with a low density of 0.28—0.31 g/cm3exhibits strain-in-fracture as high as 31.2%and thermal conductivity as low as 0.054 W/(m·K).Furthermore,a trace amount of nano-silica could effectively protect CFPA from erosion of oxidizing atmosphere in different high-temperature *** oxyacetylene ablation test of 3000°C for 20 s shows a mass ablation rate of 0.0225 g/s,a linear ablation rate of 0.209 mm/s for the modified CFPA,which are 9.64%and 24.82%lower than the unmodified ***,the long-time butane ablation test of 1200°C for 200 s shows an insignificant recession with mass and linear ablation rate of 0.079 g/s and 0.039 mm/s,16.84%and 13.33%lower than the unmodified ***,the fixed thermocouple in the test also demonstrates a good thermal insulation performance with a low peak back-face temperature of 207.7°C,12.25%lower than the unmodified ***,the nano-silica modified CFPA with excellent overall performance presents promising prospects in high-temperature aerospace applications.

关键词： Nano-silica Carbonfiber Phenolic aerogel Insulation Ablation

Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies

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World Journal of Gastroenterology 2024年第10期30卷 1295-1312页

作者： Hui ma Qing-Zhu Yan Jing-Ru ma Dong-Fu Li Jun-ling Yang Department of Clinical Laboratory The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Ultrasound Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Digestive Diseases Center Department of Hepatopancreatobiliary MedicineThe Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina Department of Respiratory and Critical Care Medicine The Second Hospital of Jilin UniversityChangchun 130000Jilin ProvinceChina

Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease *** review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and *** delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive *** factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are ***,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease *** reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is *** strategies,including anti-viral and immunomodulatory approaches,are critically *** role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent *** conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV *** a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge *** more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient *** dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory *** role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation.

关键词： Hepatitis B virus reactivation Immunological mechanisms Disease progression management strategies Immune response