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

Communications in Theoretical Physics 2024年第7期76卷 136-146页

作者： da.cheng ma Ling-yi Cui Chu-xiao Sun Xiao-da. Chi Zheng-Nan XianYu An Du College of Science Northeastern University Department of Basic Science Dalian Naval Academy Department of Physics College of Sciences Shenyang University of Chemical Technology National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern University Key Laboratory of da.a Analytics and Optimization for Smart Industry(Northeastern University) Ministry of Education

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 theorem. By 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 other. When 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 nanoribbon. The results reveal that the magnetism of a low-dimensional spin system is different from that of a three-dimensional spin system. When 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 obtained. This work can provide a detailed theoretical basis for designing and fabricating next-generation low-dimensional magnetic random-access memory.

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

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Uniqueness Problem for the Backward Differential Equation of a Continuous-State Branching Process

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Acta mathematica Sinica,English Series 2024年第8期40卷 1825-1836页

作者： Pei sen LI Zeng Hu LI School of mathematics and Statistics Beijing Institute of TechnologyBeijing 100872P.R.China School of mathematical Sciences Beijing Normal UniversityBeijing 100875P.R.China

The distributional properties of a multi-dimensional continuous-state branching process are determined by its cumulant semigroup,which is defined by the backward differential *** provide a proof of the assertion of Rhyzhov and Skorokhod(Theory ***.,1970)on the uniqueness of the solutions to the equation,which is based on a characterization of the process as the pathwise unique solution to a system of stochastic equations.

关键词： Continuous-state branching process multi-dimensional backward differential equation stochastic equation generator

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Simultaneous Bulk-and Surface-initiated Living Polymerization Studied with a Heterogeneous Stochastic Reaction Model

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Chinese Journal of Polymer Science 2024年第3期42卷 364-372,I0008页

作者： Jia-Shu ma Zhi-Ning Huang Jia-Hao Li Bang-Ping Jiang Yan-da.Liao Shi-Chen Ji Xing-Can Shen State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources(Ministry of Education of China)School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Computer Science and Engineering&School of Software Guangxi Normal UniversityGuilin 541004China

To better characterize the properties of surface-initiated polymers, simultaneous bulk-and surface-initiated polymerizations are usually carried out by assuming that the properties of the surface-initiated polymers resemble those of the bulk-initiated polymers. Through a Monte Carlo simulation using a heterogeneous stochastic reaction model, it was discovered that the bulk-initiated polymers exhibit a higher molecular weight and a lower dispersity than the corresponding surface-initiated polymers, which indicates that the equivalent assumption is invalid. Furthermore, the molecular weight distributions of the two types of polymers are also different, suggesting different polymerization mechanisms. The results can be simply explained by the heterogeneous distributions of reactants in the system. This study is helpful to better understand surface-initiated polymerization.

关键词： Surface-initiated polymerization Polymer brush Stochastic reaction model Heterogeneous polymerization Simultaneous polymerization

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Product quality prediction based on RBF optimized by firefly algorithm

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Journal of Systems Engineering and Electronics 2024年第1期35卷 105-117页

作者： HAN Huihui WANG Jian CHEN sen YAN manting College of Electronics and Information Engineering Tongji UniversityShanghai 201804China

With the development of information technology,a large number of product quality da.a in the entire manufacturing process is accumulated,but it is not explored and used *** traditional product quality prediction models have many disadvantages,such as high complexity and low *** overcome the above problems,we propose an optimized da.a equalization method to pre-process da.aset and design a simple but effective product quality prediction model:radial basis function model optimized by the firefly algorithm with Levy flight mechanism(RBFFALM).First,the new da.a equalization method is introduced to pre-process the da.aset,which reduces the dimension of the da.a,removes redunda.t features,and improves the da.a *** the RBFFALFM is used to predict product *** expe riments conducted on real-world product quality da.asets valida.e that the new model RBFFALFM combining with the new da.a pre-processing method outperforms other previous me thods on predicting product quality.

关键词： product quality prediction da.a pre-processing radial basis function swarm intelligence optimization algorithm

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A Spleen Tyrosine Kinase’s Sky in Neuronal Degeneration

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Neuroscience Bulletin 2024年第2期40卷 273-276页

作者： Wan-Yun Zhang sen Lin Department of Neurology Xinqiao HospitalThe Second Afliated HospitalArmy Medical UniversityChongqing 400042China Chongqing Institute for Brain and Intelligence Guangyang Bay LaboratoryChongqing 400064China

With the growing elderly population,neurodegenerative disorders like Alzheimer's disease(AD)are emerging as a significant public health *** is widely acknowledged in the scientific community that the accumulation of neurotoxic aggregates,such as amyloid beta(Aβ),within the central nervous system is a major factor in the development of these ***,human genome-wide association studies have identified mutations in microglial receptors that may be linked to a number of neurodegenerative diseases[1].

关键词： Aβ Spleen Alzheimer

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Predictive factors and model valida.ion of post-colon polyp surgery Helicobacter pylori infection

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World Journal of Gastrointestinal Surgery 2024年第1期16卷 173-185页

作者： Zheng-sen Zhang Health management Center Affiliated Hospital of Shaoxing University(Shaoxing Municipal Hospital)Shaoxing 312000Zhejiang ProvinceChina

BACKGROUND Recently,research has linked Helicobacter pylori(***)stomach infection to colonic inflammation,mediated by toxin production,potentially impacting colorectal cancer *** To investigate the risk factors for post-colon polyp surgery,*** infection,and its correlation with pathologic *** Eighty patients who underwent colon polypectomy in our hospital between January 2019 and January 2023 were retrospectively *** were then randomly split into modeling(n=56)and model valida.ion(n=24)sets using *** modeling cohort was divided into an ***-infected group(n=37)and an ***-uninfected group(n=19).Binary logistic regression analysis was used to analyze the factors influencing the occurrence of *** infection after colon polyp surgery.A roadmap prediction model was established and ***,the correlation between the different pathological types of colon polyps and the occurrence of *** infection was analyzed after colon polyp *** Univariate results showed that age,body mass index(BMI),literacy,alcohol consumption,polyp pathology type,high-risk adenomas,and heavy diet were all influential factors in the development of *** infection after intestinal *** multifactorial logistic regression analysis showed that age,BMI,and type of polyp pathology were independent predictors of the occurrence of *** infection after intestinal *** area under the receiver operating characteristic curve was 0.969[95%confidence interval(95%CI):0.928–1.000]and 0.898(95%CI:0.773–1.000)in the modeling and valida.ion sets,*** slope of the calibration curve of the graph was close to 1,and the goodness-of-fit test was P>0.05 in the two *** decision analysis curve showed a high rate of return in both *** results of the correlation analysis between different pathological types and the occurrence of *** infection after colon polyp surgery showed that hyperplastic

关键词： Colon polyps Helicobacter pylori Risk factors Pathologic type Columnar graphic modeling

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Trends and hotspots in gastrointestinal neoplasms risk assessment: A bibliometric analysis from 1984 to 2022

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World Journal of Gastrointestinal Oncology 2024年第6期16卷 2842-2861页

作者： Qiang-Qiang Fu Le ma Xiao-Min Niu Hua-Xin Zhao Xu-Hua Ge Hua Jin De-Hua Yu sen Yang Department of General Practice Yangpu HospitalSchool of MedicineTongji UniversityShanghai 200090China Shanghai General Practice and Community Health Development Research Center Shanghai 200090China Department of Shanghai Lung Cancer Center Shanghai Chest HospitalShanghai Jiao Tong University School of MedicineShanghai 200030China Department of Oncology Shanghai Tenth People’s HospitalTongji University School of MedicineShanghai 200090China

BACKGROUND Gastrointestinal neoplasm(GN)significantly impact the global cancer burden and mortality,necessitating early detection and *** the evolution and current state of research in this field is *** To conducts a comprehensive bibliometric analysis of publications from 1984 to 2022 to elucida.e the trends and hotspots in the GN risk assessment research,focusing on key contributors,institutions,and thematic *** This study conducted a bibliometric analysis of da.a from the Web of Science Core Collection da.abase using the"bibliometrix"R package,VOSviewer,and *** analysis focused on the distribution of publications,contributions by institutions and countries,and trends in *** methods included da.a synthesis,network analysis,and visualization of international collaboration *** This analysis of 1371 articles on GN risk assessment revealed a notable evolution in terms of research focus and *** highlights the United States'critical role in advancing this field,with significant contributions from institutions such as Brigham and Women's Hospital and the National Cancer *** last five years,substantial advancements have been made,representing nearly 45%of the examined *** rates have dramatically increased,from 20 articles in 2002 to 112 in 2022,reflecting intensified research *** study underscores a growing trend toward interdisciplinary and international collaboration,with the Journal of Clinical Oncology standing out as a key publication *** shift toward more comprehensive and collaborative research methods marks a significant step in addressing GN *** This study underscores advancements in GN risk assessment through genetic analyses and machine learning and reveals significant geographical disparities in research *** calls for enhanced global collaboration and integration of artificial intelligence to improve cancer p

关键词： Gastrointestinal neoplasms Bibliometric analysis Risk assessment Network analysis Research trends

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Covalent triazine frameworks modified by ultrafine Pt nanoparticles for efficient photocatalytic hydrogen production

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Nano Research 2024年第6期17卷 4908-4915页

作者： Xu Han Xueying Ge Wen-Wen He Wangwang Shen Tao Zhou Jian-sen Wang Rong-Lin Zhong Abdullah mal-Enizi Ayman Nafady Shengqian ma School of Chemistry and Life Science Advanced Institute of Materials ScienceChangchun University of TechnologyChangchun 130012China Laboratory of Theoretical and Computational Chemistry Institute of Theoretical ChemistryCollege of ChemistryJilin UniversityChangchun 130021China Department of Chemistry University of North Texas1508 W.Mulberry St.DentonTX 76201USA Department of Chemistry College of ScienceKing Saud UniversityRiyadh 11451Saudi Arabia

Pt nanoparticles(PtNPs)as active species have always been considered as one of the best semiconductor materials for photocatalytic hydrogen *** this study,a Schottky heterojunction has been successfully constructed by evenly loading ultrafine PtNPs onto a triazine-based covalent organic frameworks(COFs).This strategy maintained the high activity of these ultra-small PtNPs while maximizing the utilization of the Pt active *** fabricated PtNPs@covalent triazine-based framework-1(CTF-1)composite accomplished a significantly high rate of hydrogen evolution(20.0 mmol·g^(−1)·h^(−1),apparent quantum efficiency(AQE)=7.6%,atλ=450 nm)with 0.40 wt.%Pt loading,giving rise to a 44-fold-increase in the efficiency of the photocatalytic hydrogen production compared to the pristine *** calculations revealed that the strong electron transfer(Q(Pt)=−0.726 qe,in the analysis of Bader charge,Q(Pt)is the charge quantity transferred from Pt cluster to CTF-1,and qe is the unit of charge transfer quantity)between PtNPs and CTF-1 triggers a strong interaction,which makes PtNPs being firmly attached to the structure of CTF-1,thereby enabling high stability and excellent hydrogen production ***,the hydrogen binding free energy(ΔGH*)of PtNPs@CTF-1 is much lower than that of the unmodified CTF-1,leading to a much lower intermediate state and hence a significant improvement in photocatalytic *** overall findings of this work provide a new platform to incorporate metallic NPs into COFs for the design and fabrication of highly efficient photocatalysts.

关键词： Pt nanoparticles covalent triazine-based framework-1(CTF-1) photocatalysts hydrogen evolution reaction

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Identification of carbonates with high positive carbon isotope excursion from the Liaohe Group in the northeastern North China Craton and implications for the Lomagundi-Jatuli Event

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Science China Earth Sciences 2024年第9期67卷 2824-2844页

作者： Hongyu WANG Shuanhong ZHANG sen WANG Linghao KONG Yue ZHAO Qiqi ZHANG sen GAO Guohui HU Institute of Geomechanics Chinese Academy of Geological Sciences Key Laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural Resources SinoProbe Laboratory Chinese Academy of Geological Sciences School of Earth Science and Mineral Resources China University of Geosciences

The Great Oxida.ion Event（GOE） during the early Paleoproterozoic represents the first significant buildup in Earth's atmospheric oxygen and resulted in a series of significant changes in the Earth's surface environment. Among them is the 2.22（or 2.33）–2.06 Ga Lomagundi-Jatuli Event（LJE）, which is globally, the largest magnitude and longest duration, marine carbonate positive carbon isotope excursion(δ13CV-PDB>10‰) known. This event has attracted the attention of scholars all over the world. However, except for a high positive carbon isotope excursion(δ13CV-PDB>10‰) recently identified from marine carbonate rocks within the da.oshan Formation in the lower Fanhe Group（or the Sanchazi Group） in the Longgang Block in the northeast North China Craton（NCC）, Paleoproterozoic carbonates in the NCC are characterized by a low-amplitude positive carbon isotope excursion(δ13CV-PDBmajor and trace element geochemical analyses of Liaohe Group carbonate rocks from the Anshan area in the northwestern margin of the Jiao-Liao-Ji Belt in the northeast NCC. Our results show that the Gaojiayu Formation of the Liaohe Group in the Anshan area has high positive δ13CV-PDBvalues from 8.6‰ to 12.4‰ and δ18OV-SMOWvalues of 17.9‰–27.4‰(δ18OV-PDBvalues ranging from-12.6‰ to-3.4‰). This provides solid evidence for the preservation of reliable sedimentary records of the LJE in the northeastern NCC. Deposition of the high positive δ13C excursion（>10‰） of marine carbonate rocks occurred at about 2.15 *** comparisons of different s

关键词： Lomagundi-Jatuli Event (LJE) Great Oxida.ion Event (GOE) Carbon-oxygen isotopes Liaohe Group marine carbonate Jiao-Liao-Ji Belt North China Craton

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Advancements in machine learning for material design and process optimization in the field of additive manufacturing

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China Foundry 2024年第2期21卷 101-115页

作者： Hao-ran Zhou Hao Yang Huai-qian Li Ying-chun ma.sen Yu Jian shi Jing-chang Cheng Peng Gao Bo Yu Zhi-quan Miao Yan-peng Wei National Key Laboratory of Advanced Casting Technologies Shenyang Research Institute of Foundry Co.Ltd.CAMShenyang 110022China Department of Mechanical Engineering Tsinghua UniversityBeijing 100084China Key Laboratory of Space Physics Beijing 100076China School of materials Science and Engineering Nanyang Technological University639798Singapore

Additive manufacturing technology is highly regarded due to its advantages,such as high precision and the ability to address complex geometric ***,the development of additive manufacturing process is constrained by issues like unclear funda.ental principles,complex experimental cycles,and high *** learning,as a novel artificial intelligence technology,has the potential to deeply engage in the development of additive manufacturing process,assisting engineers in learning and developing new *** paper provides a comprehensive overview of the research and applications of machine learning in the field of additive manufacturing,particularly in model design and process ***,it introduces the background and significance of machine learning-assisted design in additive manufacturing *** then further delves into the application of machine learning in additive manufacturing,focusing on model design and process ***,it concludes by summarizing and forecasting the development trends of machine learning technology in the field of additive manufacturing.

关键词： additive manufacturing machine learning material design process optimization intersection of disciplines embedded machine learning

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