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FCC-to-HCP Phase Transformation in CoCrNi_x Medium-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2020年第8期33卷 1151-1158页

作者： jia-Qi Zhao hua Tian Zhong wang Xue-jiao wang Jun-Wei Qiao College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China College of Information and Computer Taiyuan University of TechnologyTaiyuan 030024China

A hybrid first-principles/Monte Carlo simulation is combined with experiments to study the structure and elastic properties of CoCrNi_x(x=1-0.5)*** experimental X-ray diffraction patterns show that the structures have changed from the single-phase face-centered cubic(FCC)structure at x=1-0.8 to the coexistence of FCC and the hexagonal close-packed structures at x=0.7-0.5,which is further confirmed by calculations on mixing *** elastic moduli by calculation are basically in agreement with ***-temperature tension shows that the six alloys have a certain plasticity,the strength and plasticity of the alloys have a linear decrease with the decrease in Ni contents,and the plasticity of the alloys drops from 84 to 23%.Furthermore,first-principles density function theory calculations were employed to reveal the electronic and magnetic structures of *** electron density of states for all alloys is asymmetrical,which illustrates that the alloys are *** is found that Cr atoms can suppress the ferromagnetism of alloys,since Cr atoms have both positive and negative magnetic moments in all alloys.

关键词： Hexagonal close-packed(HCP)structure Medium-entropy alloys Magnetic Mechanical properties Phase transformation High-entropy alloys

Task assignment in ground-to-air confrontation based on multiagent deep reinforcement learning

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Defence Technology（防务技术） 2023年第1期19卷 210-219页

作者： jia-yi Liu Gang wang Qiang Fu Shao-hua Yue Si-yuan wang Air and Missile Defense College Air Force Engineering UniversityXi'an710051China Air Force Engineering University Changle East RoadXi'anShaanxi710051China

The scale of ground-to-air confrontation task assignments is large and needs to deal with many concurrent task assignments and random *** at the problems where existing task assignment methods are applied to ground-to-air confrontation,there is low efficiency in dealing with complex tasks,and there are interactive conflicts in multiagent *** study proposes a multiagent architecture based on a one-general agent with multiple narrow agents(OGMN)to reduce task assignment *** the slow speed of traditional dynamic task assignment algorithms,this paper proposes the proximal policy optimization for task assignment of general and narrow agents(PPOTAGNA)*** algorithm based on the idea of the optimal assignment strategy algorithm and combined with the training framework of deep reinforcement learning(DRL)adds a multihead attention mechanism and a stage reward mechanism to the bilateral band clipping PPO algorithm to solve the problem of low training ***,simulation experiments are carried out in the digital *** multiagent architecture based on OGMN combined with the PPO-TAGNA algorithm can obtain higher rewards faster and has a higher win *** analyzing agent behavior,the efficiency,superiority and rationality of resource utilization of this method are verified.

关键词： Ground-to-air confrontation Task assignment General and narrow agents Deep reinforcement learning Proximal policy optimization(PPO)

Efficient distributed algorithms for holistic aggregation functions on random regular graphs

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Science China(Information Sciences) 2022年第5期65卷 32-50页

作者： Lin jia Qiang-Sheng hua Haoqiang FAN Qiuping wang Hai JIN National Engineering Research Center for Big Data Technology and System/Services Computing Technology and System Lab/Cluster and Grid Computing Lab School of Computer Science and TechnologyHuazhong University of Science and Technology Institute for Interdisciplinary Information Science Tsinghua University

In this paper, we propose efficient distributed algorithms for three holistic aggregation functions on random regular graphs that are good candidates for network topology in next-generation data *** three holistic aggregation functions include SELECTION（select the k-th largest or smallest element）,DISTINCT（query the count of distinct elements）, MODE（query the most frequent element）. We design three basic techniques — Pre-order Network Partition, Pairwise-independent Random Walk, and Random Permutation Delivery, and devise the algorithms based on the techniques. The round complexity of the distributed SELECTION is Θ（log N） which meets the lower bound where N is the number of nodes and each node holds a numeric element. The round complexity of the distributed DISTINCT and MODE algorithms are O（log;N/log log N） and O（log;N log log N） respectively. All of our results break the lower bounds obtained on general graphs and our distributed algorithms are all based on the CON GE S T model, which restricts each node to send only O（log N） bits on each edge in one round under synchronous communications.

关键词： distributed algorithms holistic aggregation function random regular graph \({\cal C}{\cal O}{\cal N}{\cal G}{\cal E}{\cal S}{\cal T}\) model communication complexity round complexity

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Size and Dynamics of Ring Polymers under Different Topological Constraints

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Chinese Journal of Polymer Science 2023年第4期41卷 516-524,I0006页

作者： jiang-Yang Mo Zhen-hua wang Yu-Yuan Lu Li-jia An State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun130022China University of Science and Technology of China Hefei230026China

The impact of ring polymer length N and the influence of interchain and intrachain interactions on the size and dynamic behaviors of ring polymers,including the structural relaxation time τ_(R) and self-diffusion coefficient D,remain poorly understood at present due to a lack of systematic studies with relatively large N *** work addressed this issue by applying dynamic Monte Carlo simulations with independently tuned interchain and intrachain interactions to investigate the size and dynamics of the ring melts with chain lengths over a wide range of 0.2N_(e)≤N≤80N_(e)(N_(e) is the entanglement length of corresponding linear chains)under different topological constraints,including all-crossing and intercrossing *** found that it was inappropriate to treat the unknotting constraint free energy of the ring chains in the melts as the free energy contributed by the excluded volume interactions of polymers in a good *** exponents of 2.5 and 1.5 reflecting the Ndependence of τ_(R) were obtained for long ring chains in non-crossing and intra-crossing systems,respectively,suggesting that the ring chains behaved as individual clusters and exhibited Zimm-like dynamics in intra-crossing systems.A single scaling exponent of-2 reflecting the Ndependence of D was obtained for ring chains in non-crossing and intra-crossing systems,indicating that the intrachain constraints affected only the value of D,and had little influence on the scaling relationship between D and ***,the extended Stokes-Einstein relation broke down for the ring chains in the non-crossing and intra-crossing systems because the structural relaxation and translational diffusion were decoupled for the short ring systems,while both the translational diffusion and rotational relaxations,as well as diffusion at short and long time scales,were decoupled for long ring systems.

关键词： Ring polymer Topological constraint Extended Stokes-Einstein relation Monte Carlo simulation

On the Conditional Bounds for Siegel Zeros

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Acta Mathematica Sinica,English Series 2022年第5期38卷 869-876页

作者： Chao hua jia Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China hua Loo-Keng Key Laboratory of Mathematics Chinese Academy of SciencesBeijing 100190P.R.China School of Mathematical Sciences University of Chinese Academy of SciencesBeijng 100049P.R.China

In this paper,under a weakened version of Hardy–Littlewood Conjecture on the number of representations in Goldbach problem,we shall prove bounds for the Siegel zeros of real primitive Dirichlet characters for composi... 详细信息

关键词： Siegel zero Goldbach problem

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu Xiao-Li Li Xiao-Ting Sun Li-Ting wang Xia Wu Ling-Jie Zhu Xiao-jia Yang Qian-Ru He Fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

VARIATIONAL ITERATION SOLVING METHOD FOR SEA-AIR OSCILLATOR MODEL OF INTERDECADAL CLIMATE FLUCTUATIONS

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Chinese Geographical Science 2005年第3期15卷 227-230页

作者： MO jia-qi LIN Yi-hua wang Hui Department of Mathematics A nhui Normal University Wuhu 241000 P. R. China Division of Computational Science E-Institutes of Shanghai Universities at Shanghai Jiaotong University Shanghai 200240 P. R. China Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 P. R. China Chinese Academy of Meteorological Sciences Beijing 100081 P. R. China

Atmospheric physics is a very complicated natural phenomenon and needs to simplify its basic models for the sea-air oscillator. And it is solved by using the approximate method. The variational iteration method is a simple and valid method. In this paper the coupled system for a sea-air oscillator model of interdecadal climate fluctuations is considered. Firstly, through introducing a set of functions, and computing the variations, the Lagrange multipliers are obtained. And then, the generalized expressions of variational iteration are constructed. Finally, through selecting appropriate initial iteration from the iteration expressions, the approximations of solution for the sea-air oscillator model are solved successively.

关键词： nonlinear variational iteration El Nino-Southern Oscillator model

2016年7月19——20日济南暴雨过程分析

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安徽农业科学 2017年第6期45卷 200-204页

作者：刘新彦褚颖佳王华赵玉翠张悦山东省济阳县气象局山东济阳251400 山东省济南市气象局山东济南250102

利用常规观测资料,从环流形势、物理量场和雷达资料等方面,对2016年7月19—20日发生在济南地区的暴雨天气过程进行综合分析,并对其数值预报进行了检验。结果表明,这是一次由低涡、切变线、低空急流和黄淮气旋共同作用产生的暴雨。暴雨... 详细信息

利用常规观测资料,从环流形势、物理量场和雷达资料等方面,对2016年7月19—20日发生在济南地区的暴雨天气过程进行综合分析,并对其数值预报进行了检验。结果表明,这是一次由低涡、切变线、低空急流和黄淮气旋共同作用产生的暴雨。暴雨过程发生在气旋暖区,为层状云和积状云混合云降水,降雨范围大、效率高;对流性的特征仅表现为短时强降水,雨量分布相对于单纯的积云降雨更均匀。数值模式对此次过程的强降雨时段的预报普遍较好,但由于预报的气旋路径较实况更偏东,造成降雨量级上大多偏大。

关键词：暴雨环流形势物理量场雷达资料

Two Indium(III)-based Fluorescent Metal-Organic Frameworks for Highly Sensing Fe^(3+),2,4-DNP,and TNP

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Chemical Research in Chinese Universities 2024年第1期40卷 119-126页

作者： wang Dan LI Wen LI Guanghua hua jia LIU Yunling State Key Laboratory of Inorganic Synthesis&Preparative Chemistry Jilin UniversityChangchun130012P.R.China

Two novel metal-organic frameworks(MOFs),JLU-MOF130([In(NH2−BDC)(Imi)(1H−Imi)]·DMF·H2O,NH2−H2BDC=2-aminobenzene-1,4-dicarboxylic acid,1H−Imi=1H-imidazole,DMF=N,N-dimethylformamide)and JLU-MOF131([In(1,4-NDC)(Imi)(1H−Imi)]·DMF0.5,1,4-H_(2)NDC=1,4-naphthalene-dicarboxylic acid),were ***-MOF130 features a three-dimensional(3D)architecture with a neb ***-MOF131 is characterized by a two-dimensional(2D)structure with an sql ***-MOF130 has excellent fluorescence detection performance towards Fe^(3+),2,4-dinitrophenol(2,4-DNP),and 2,4,6-trinitrophenol(TNP),but the fluorescence detection performance of JLU-MOF131 is further improved by converting NH2−H2BDC to more conjugated 1,4-H_(2)*** Stern-Volmer(SV)quenching constant(KSV)values of JLU-MOF130 sensing 2,4-DNP,TNP,and Fe^(3+)are 5.24×10^(4),4.44×10^(4),and 4.73×10^(3) L/mol,*** corresponding limit of detection(LOD)values are 1.17,1.36,and 14.59µmol/*** KSV values for JLU-MOF131 are 1.26×10^(5),9.02×10^(4),and 8.48×103 L/mol,and the corresponding LOD values are 0.35,0.42,and 3.60µmol/L,***,the emission wavelengths of the two MOFs obviously shift as the fluorescence emission intensities decrease upon the addition of 2,4-DNP and TNP,which can be applied in selective detection.

关键词： Metal-organic framework Fluorescence quenching Fe^(3+) 2 4-Dinitrophenol(2 4-DNP) 2 4 6-Trinitrophenol(TNP)