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The Mechanism of Heating Rate on the Secondary Recrystallization Evolution in Grain Oriented Silicon Steel

Journal of Wuhan University of Technology(Materials Science) 2025年第1期 275-282页

作者：高倩 LI jun WANG Xianhui CAO Laifu gong Jian LI Bo Central Iron and Steel Research Institute Group Shougang Zhixin Electromagnetic Material R&D (Beijing) Co. Ltd. Beijing Shougang Co. Ltd.

Grain-oriented silicon steels were prepared at different heating rates during high temperature annealing, in which the evolution of magnetic properties, grain orientations and precipitates were studied. To illustrate the Zener factor, the diameter and number density of precipitates of interrupted testing samples were statistically calculated. The effect of precipitate ripening on the Goss texture and magnetic property was investigated. Data indicated that the trend of Zener factor was similar under different heating rates, first increasing and then decreasing, and that the precipitate maturing was greatly inhibited as the heating rate increased. Secondary recrystallization was developed at the temperature of 1 010 ℃ when a heating rate of 5 ℃/h was used, resulting in Goss, Brass and {110} oriented grains growing abnormally and a magnetic induction intensity of 1.90T. Furthermore, increasing the heating rate to 20 ℃/h would inhibit the development of undesirable oriented grains and obtain a sharp Goss texture. However, when the heating rate was extremely fast, such as 40 ℃/h, poor secondary recrystallization was developed with many island grains, corresponding to a decrease in magnetic induction intensity to 1.87 T. At a suitable heating rate of 20 ℃/h, the sharpest Goss texture and the highest magnetic induction of 1.94 T with an onset secondary recrystallization temperature of 1 020 ℃ were found among the experimental variables in this study. The heating rate affected the initial temperature of secondary recrystallization by controlling the maturation of precipitates, leading to the deviation and dispersion of Goss texture, thereby reducing the magnetic properties.

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人体形态参数的因子分析

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体育科研 2004年第1期25卷 41-43页

作者：侯曼龚也君刘静民北京师范大学体育与运动学院北京100875 北京师范大学数学系北京100875 清华大学体育部北京100084

采用实验法对研究对象进行32项人体形态参数因子分析,结果发现有两个公共因子可以反映32项人体形态参数中的绝大部分信息,分别可以解释为体重因子和身高因子,从而从另一个角度验证了以体重和身高作为计算人体惯性参数的回归方程中的自变... 详细信息

采用实验法对研究对象进行32项人体形态参数因子分析,结果发现有两个公共因子可以反映32项人体形态参数中的绝大部分信息,分别可以解释为体重因子和身高因子,从而从另一个角度验证了以体重和身高作为计算人体惯性参数的回归方程中的自变量,具有相当的代表性,可以反映人体形态的绝大部分信息。但人体骨盆的宽度,手的大小、宽窄,头的大小以及足的长短、宽窄等不完全由体重和身高决定。

关键词：因子分析形态参数公共因子身高体重人体

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Distribution of atrazine in a crop-soil-groundwater system at Baiyangdian Lake area in China

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Journal of Environmental Sciences 2001年第2期13卷 148-152页

作者： ye Chang ming gong Ai jun WANG Xing jun ZHENG He hui LEI Zhi fang Research Center for Eco Environmental Sciences Chinese Academy of SciencesBeijing 100085China.

In this paper, the concentration distribution and environmental fate of atrazine in a crop soil groundwater system at Baiyangdian Lake area of North China were studied. The concentration of the herbicide in spatial and vertical soils, and in roots, stem, leaf, corncob and kernel of corn, and in groundwater were measured by HPLC. The results showed that the variation of spatial concentration of atrazine in soil can be described by first order kinetics equation which has a half life of 360 days and a rate constant of 0.0019d -1 . The vertical variation of atrazine concentration with soil depth follows the exponential decay law. After 120 days following atrazine application, the mass distributions of this herbicide in crop soil groundwater system are 71% in soil, 20% in groundwater and 1% in crop respectively, and 8% due to loss by degradation or often removal processes. The order of atrazine concentration in every part of corn crop is in roots>in corncob>in kernel of corn>in leaf.

关键词： atrazine soil corn crop groundwater fate China

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Adaptive tracking control for air-breathing hypersonic vehicles with state constraints

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 599-614页

作者： gong-jun LI Science and Technology on Space Intelligent Control Laboratory Beijing Institute of Control EngineeringBeijing 100190China

We investigate the adaptive tracking problem for the longitudinal dynamics of state-constrained airbreathing hypersonic vehicles, where not only the velocity and the altitude, but also the angle of attack(AOA) is required to be tracked. A novel indirect AOA tracking strategy is proposed by viewing the pitch angle as a new output and devising an appropriate pitch angle reference trajectory. Then based on the redefined outputs(i.e., the velocity,the altitude, and the pitch angle), a modified backstepping design is proposed where the barrier Lyapunov function is used to solve the state-constrained control problem and the control gain of this class of systems is *** analysis is given to show that the tracking ob jective is achieved, all the closed-loop signals are bounded,and all the states always satisfy the given constraints. Finally, numerical simulations verify the effectiveness of the proposed approach.

关键词： Hypersonic vehicle Constraints Output redefinition Barrier Lyapunov function

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Neighborhood co-occurrence modeling in 3D point cloud segmentation

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Computational Visual Media 2022年第2期8卷 303-315页

作者： Jingyu gong Zhou ye Lizhuang Ma Department of Computer Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China Shanghai CLS Fintech Co. LTDShanghai 200030China MoE Key Lab of Artificial Intelligence Shanghai Jiao Tong UniversityShanghai 200240China

A significant performance boost has been achieved in point cloud semantic segmentation by utilization of the encoder-decoder architecture and novel convolution operations for point ***,co-occurrence relationships within a local region which can directly influence segmentation results are usually ignored by current *** this paper,we propose a neighborhood co-occurrence matrix(NCM)to model local co-occurrence relationships in a point *** generate target NCM and prediction NCM from semantic labels and a prediction map ***,Kullback-Leibler(KL)divergence is used to maximize the similarity between the target and prediction NCMs to learn the co-occurrence ***,for large scenes where the NCMs for a sampled point cloud and the whole scene differ greatly,we introduce a reverse form of KL divergence which can better handle the difference to supervise the prediction *** integrate our method into an existing backbone and conduct comprehensive experiments on three datasets:Semantic3D for outdoor space segmentation,and S3DIS and ScanNet v2 for indoor scene *** indicate that our method can significantly improve upon the backbone and outperform many leading competitors.

关键词： 3D vision point cloud co-occurrence relation modeling semantic segmentation

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Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： Qing He Zhen Wang Yuchen Wang Mengjie Zhu Zhile Liang Kanghong Zhang Yuge Xu gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期 46-95页

作者： Zhong-Liang gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

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Effect of aspect ratio on triaxial compression of multi-sphere ellipsoid assemblies simulated using a discrete element method

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Particuology 2017年第3期15卷 49-62页

作者： Jian gong jun Liu State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China

Here, we present a numerical investigation of the mechanical behavior of ellipsoids under triaxial com- pression for a range of aspect ratios. Our simulations use a multi-sphere approach in a three-dimensional discrete element method. All assemblies were prepared at their densest condition, and triaxial compres- sion tests were performed up to extremely large strains, until a critical state was reached. The stress-strain relationship and the void ratio-strain behavior were evaluated. We found that the stress-dilatancy rela- tionship of ellipsoids with different aspect ratios could be expressed as a linear equation. In particular, the aspect ratio influenced the position of the critical state lines for these assemblies. Particle-scale char- acteristics at the critical state indicate that particles tend to be flat lying, and the obstruction of particle rotation that occurs with longer particles affects their contact mechanics. Lastly, anisotropic coefficients related to aspect ratio were investigated to probe the microscopic origins of the macroscopic behavior. A detailed analysis of geometrical and mechanical anisotropies revealed the microscopic mechanisms underlying the dependency of peak and residual strengths on aspect ratio.

关键词： EllipsoidsAspect ratio DEM Triaxial compression Particle shape Macro-micro response

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黄土高原森林林下植被物种多样性及其影响因素

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东北林业大学学报 2025年第2期53卷 66-74页

作者：宫正黄河文明与可持续发展研究中心(河南大学) 开封475001

以黄土高原不同密度刺槐(Robinia pseudoacacia)林为研究对象,通过调查样地的地形及土壤理化性质,利用方差分析、线性拟合、冗余分析等方法,分析林下植被物种多样性特征,探究影响林下植被物种多样性的因素。结果表明:不同林分密度的刺... 详细信息

以黄土高原不同密度刺槐(Robinia pseudoacacia)林为研究对象,通过调查样地的地形及土壤理化性质,利用方差分析、线性拟合、冗余分析等方法,分析林下植被物种多样性特征,探究影响林下植被物种多样性的因素。结果表明:不同林分密度的刺槐林林下植被物种多样性存在显著差异(P<0.05)。刺槐林下灌木Margalef丰富度指数随坡向的增大而减小,林下草本植物Margalef丰富度指数随坡度的增加而减小。刺槐林下灌木植物物种多样性的主要影响因素是密度、坡向、土壤全氮质量分数、土壤铵态氮质量分数,草本植物物种多样性的主要影响因素是土壤速效磷质量分数。

关键词：刺槐林物种多样性影响因素冗余分析黄土高原

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Analyzing Asymmetric City Connectivity by Toponym on Social Media in China

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Chinese Geographical Science 2021年第1期31卷 14-26页

作者： ye Xinyue gong junfang LI Shengwen Department of Landscape Architecture and Urban Planning Texas A&M University College StationTX 77843 USA School of Geography and Information Engineering China University of GeosciencesWuhan 430074China Key Laboratory of Urban Land Resources Monitoring and Simulation Ministry of Natural ResourcesShenzhen 518034China

The connectedness between cities has become one of the most widely discussed topics in urban and regional research in the mobile and big data era. One problem identified is the asymmetric city connectivity, partially due to data availability. We present a data-driven approach based on location and toponym(place name) extracted from social media data, to assess the asymmetric connectivity between cities. The assumption is that a higher frequency of occurrences of the name of city i in posts located in city j would imply that the city i is more influential than other cities upon city j. In addition, we’ve developed a group of measurements such as the relatedness index, impact index, link strength index, dependence index, and structure similar index to characterize such interactions. This framework of connectivity measurements can also be used to support smart planning taking into account the evolving interplay among cities. The space-time structure of urban systems in China is examined as the case study.

关键词： asymmetric city connectivity social media urban system China

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