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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 1009-1018页

作者： Hong-di Zhang Xiao-yu li Jing Pang li-juan yin Hai-jian Ma ying-jie li Yan liu Wei-min Wang Key Laboratory for liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Qingdao Yunlu Energy Technology Co. Ltd. School of Mechanical and Electrical Engineering Weifang University

The corrosion behavior and microstructure of Fe78Si9B13 glassy alloy in NaOH and NaCl solutions under a 0.02-T magnetic field were investigated through electrochemical testing and scanning electron microscopy （SEM）. The current-density prepeak （PP） in the anodic polarization curves in low-concentration NaOH solutions （classified as type I） tends to disappear when the NaOH concentration is increased to 0.4 mol/L and the magnetic field is applied. Under the magnetic field, the height of the second current-density peak is increased in low-concentration NaOH solutions （type I） but decreased in high-concentration NaOH solutions （type Ⅱ）. The non-monotonic effect of the magnetic field was similarly observed in the case of polarization curves of samples measured in NaCl solutions, Ring-like corroded patterns and round pits are easily formed under the magnetic field in NaOH and NaC1 solutions. These experimental results were discussed in terms of the magnetohydrodynamic （MHD） effect.

关键词： amorphous alloys electrochemical behavior magnetic field anodic polarization micrographs

Ultrasmall barium titanate nanoparticles modulated stretchable dielectric elastomer sensors with large deformability and high sensitivity

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InfoMat 2023年第8期5卷 94-106页

作者： Zun-Peng Feng Ya-Nan Hao Jing Qin Shao-Long Zhong Ke Bi Yu Zhao li-juan yin Jia-Yao Pei Zhi-Min Dang State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijingthe People's Republic of China State Key Laboratory of Power System Department of Electrical EngineeringTsinghua UniversityBeijingthe People's Republic of China Beijing University of Posts and Telecommunications Research Institute Shenzhenthe People's Republic of China School of Electrical Engineering Zheng Zhou UniversityZhengZhouthe People's Republic of China

Large deformability and high sensitivity is difficult to be realized simultaneously in flexible ***,taking advantage of the high permittivity and highly active surfaces of the ultrasmall barium titanate nanoparticles(BT NPs)and the high stretchability of the p(BA-GMA)elastomer matrix,we propose a high-performance soft stretchable *** addition of the ultrasmall BT NPs can not only increase the permittivity and capacitance of polyacrylate-matrix composite dielectric material to obtain a high sensitivity,but also basically maintains the excellent mechanical properties of the polymer *** dielectric constants of the composite films increase from 5.68 to 13.13 at 10 kHz with the increase of BT NPs content from 0 to 15 vol.%,which results in a high capacitance of 236.16 pF for 15 vol.%BT/p(BA-GMA)*** the high permittivity and the large deformability(a maximal deformation of 87.2%),the 15 vol.%BT/p(BA-GMA)sensor has high sensitivity and shows high linearity and stable output even if under dynamic *** dual-mode sensor that utilizes the orthogonality of capacitance-resistance is designed,which shows excellent performance in monitoring human body movements and noncontact *** results present that the BT/p(BA-GMA)-based sensor has high stability and reliability not exceed 65C,which can meet the application requirements in dynamic monitoring.

关键词： barium titanate composite dielectric elastomer nanoparticles stretchable sensor

Dynamic modeling and RBF neural network compensation control for space flexible manipulator with an underactuated hand

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Chinese Journal of Aeronautics 2024年第3期37卷 417-439页

作者： Dongyang SHANG Xiaopeng li Meng yin Fanjie li School of Mechanical Engineering and Automation Northeastern UniversityShenyang 110819China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

In space operation,flexible manipulators and gripper mechanisms have been widely used because of light weight and ***,the vibration caused by slender structures in manipulators and the parameter perturbation caused by the uncertainty derived from grasping mass variation cannot be *** existence of vibration and parameter perturbation makes the rotation control of flexible manipulators difficult,which seriously affects the operation accuracy of ***’s more,the complex dynamic coupling brings great challenges to the dynamics modeling and vibration *** solve this problem,this paper takes the space flexible manipulator with an underactuated hand(SFMUH)as the research *** dynamics model considering flexibility,multiple nonlinear elements and disturbance torque is established by the assumed modal method(AMM)and Hamilton’s principle.A dynamic modeling simplification method is proposed by analyzing the nonlinear ***’s more,a sliding mode control(SMC)method combined with the radial basis function(RBF)neural network compensation is ***,the control law is designed using a saturation function in the control method to weaken the chatter *** the help of neural networks to identify the uncertainty composition in the SFMUH,the tracking accuracy is *** results of ground control experiments verify the advantages of the control method for vibration suppression of the SFMUH.

关键词： Space flexible manipulator RBF neural network Underactuated hand Dynamic models Model simplification

cKBET:assessing goodness of batch effect correction for single-cell RNA-seq

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Frontiers of Computer Science 2024年第1期18卷 215-228页

作者： Yameng ZHAO yin GUO limin li School of Mathematics and Statistics Xi’an Jiaotong UniversityXi’an 710049China

Single-cell RNA sequencing reveals the gene structure and gene expression status of a single cell,which can reflect the heterogeneity between ***,batch effects caused by non-biological factors may hinder data integration and downstream *** the batch effect can be evaluated by visualizing the data,which actually is subjective and *** this work,we propose a quantitative method cKBET,which considers the batch and cell type information *** cKBET method accesses batch effects by comparing the global and local fraction of cells of different batches in different cell *** verify the performance of our cKBET method on simulated and real biological data *** experimental results show that our cKBET method is superior to existing methods in most *** general,our cKBET method can detect batch effect with either balanced or unbalanced cell types,and thus evaluate batch correction methods.

关键词： single-cell RNA-seq dataset b batch effect assessment cKBET method

Metal complexes of bipyridine-functionalized covalent organic frameworks as efficient electrocatalysts for oxygen evolution reaction

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Rare Metals 2024年第7期43卷 3096-3106页

作者： Zhuang-Zhuang Wu Tian Xia ying liang Yong-Peng li Zhu-yin Sui li-juan Feng Dao-Xiong Wu Xin-Long Tian Qi Chen State Key Laboratory of Marine Resource Utilization in South China Sea School of Marine Science and EngineeringHainan UniversityHaikou 570228China School of Chemistry and Chemical Engineering Yantai UniversityZhuhai519041China School of Bioengineering Zhuhai Campus of Zunyi Medical UniversityZhuhai519041China

Electrocatalytic water splitting is considered a clean and practic al method for producing *** this study,COF-Bpy,a bipyridine-functionalized covalent organic framework(COF),was prepared via post-synthetic modification,after which electrocatalysts for the oxygen evolution reactions(OER)were formed through coordination to single-or double-transition metals(Fe,Co,Ni,FeCo,FeNi or CoNi).COF-Bpy@FeNi delivered the best OER performance among the studied electrocatalysts,with an overpotential of 399 mV at 10 mA·cm^(-2)in an alkaline electrolyte(1.0 mol·L^(-1)KOH aqueous).Notably,the electrocatalytic performance of COF-Bpy@FeNi showed slight degradation during durability testing,which is ascribable to its irreversible benzoquinoline structure and strong metal *** expected,COF-Bpy@FeNi exhibited a low overpotential of 347 mV at a turnover frequency(TOF)of 0.1 s^(-1),which suggests that COF-Bpy@FeNi possesses excellent intrinsic electroc atalytic OER ***,density functional theory(DFT)calculations reveal that the Ni site plays a major role,while the Fe site adjusts the electronic structure of the Ni ions,which rationalizes the excellent OER properties of COF-Bpy@*** study not only provides a simple and efficient method for complexing COFs with transition metals,but also offers a novel strategy for designing porous organic polymer electrocatalysts.

关键词： Covalent organic framework Oxygen evolution reactions(OER)electrocatalyst Nickel-iron synergy Water splitting

CircPTEN-MT from PTEN regulates mitochondrial energy metabolism

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Journal of Genetics and Genomics 2024年第5期51卷 531-542页

作者： Danhui Ruan Jiancheng Xu Yang liu juan Luo Xuyang Zhao Yuhua li Guangxi Wang Jiawen Feng Hui liang Yue yin Jianyuan Luo Yuxin yin Institute of Systems Biomedicine Department of PathologySchool of Basic Medical SciencesBeijing Key Laboratory of Tumor Systems BiologyPeking University International Cancer InstitutePeking-Tsinghua Center of Life SciencesPeking University Health Science CenterBeijing 100191China Institute of Precision Medicine Peking University Shenzhen HospitalShenzhenGuangdong 518036China Department of Pharmacology School of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China Department of Medical Genetics Center for Medical GeneticsSchool of Basic Medical SciencesPeking University Health Science CenterBeijing 100191China Soochow University Cancer Institute SuzhouJiangsu 215127China

Phosphatase and tensin homolog(PTEN)is a multifunctional gene involved in a variety of physiological and pathological *** RNAs(circRNAs)are generated from back-splicing events during mRNA processing and participate in cell biological processes through binding to RNAs or ***,PTEN-related circRNAs are largely ***,we report that circPTEN-mitochondria(MT)(hsa_circ_0002934)is a circular RNA encoded by exons 3,4,and 5 of PTEN and is a critical regulator of mitochondrial energy ***-MT is localized to mitochondria and physically associated with leucine-rich pentatricopeptide repeat-containing protein(LRPPRC),which regulates posttranscriptional gene expression in *** down circPTEN-MT reduces the interaction of LRPPRC and steroid receptor RNA activator(SRA)stem-loop interacting RNA binding protein(SliRP)and inhibits the polyadenylation of mitochondrial mRNA,which decreases the mRNA level of the mitochondrial complex I subunit and reduces mitochondrial membrane potential and adenosine triphosphate *** data demonstrate that circPTEN-MT is an important regulator of cellular energy *** study expands our understanding of the role of PTEN,which produces both linear and circular RNAs with different and independent functions.

关键词： Circular RNA LRPPRC Mitochondrial energy metabolism mtDNA post-transcriptional regulation

Relationship between physical activity and specific working memory indicators of depressive symptoms in university students

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World Journal of Psychiatry 2024年第1期14卷 148-158页

作者： Qun Zhao Xing Wang Shu-Fan li Peng Wang Xiang Wang Xin Xin Suo-Wang yin Zhao-Song yin li-juan Mao School of Physical Education Shanghai University of SportShanghai 200438China Department of Physical Education Donghua UniversityShanghai 201620China

BACKGROUND The detection rate of depression among university students has been increasing in recent years,becoming one of the main psychological diseases that endangers their physical and mental *** to statistics,self-harm and suicide,for which there is no effective intervention,are the second leading causes of *** To explore the relationship between different elements and levels of physical activity and college students’depression-symptom-specific working memory *** Of 143 college students were analyzed using the Beck Depression Self-Rating Scale,the Physical Activity Rating Scale,and the Working Memory *** There was a significant difference between college students with depressive symptoms and healthy college students in completing verbal and spatial working memory(SWM)tasks correctly(all P0.05).CONCLUSION An increase in physical exercise among college students,particularly medium-and high-intensity exercise and exercise of 30 min or more,can improve the correct rate of completing working memory tasks.

关键词： Physical activity Depression symptoms University students Working memory

Characteristics of Bi-2223 HTS Tapes Under Short-Circuit Current Impacts in Hybrid Energy Transmission Pipelines

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 736-745页

作者： Yuguang Sun Chao yin Weizhen li Xinyang li Xiaohua Jiang Department of Electric Engineering Tsinghua UniversityBeijing 100084China

A hybrid energy transmission pipeline is proposed with the aim of long-distance cooperative transmission of electricity and chemical fuels, which is composed of an inner high-temperature superconducting (HTS) power cable and outer liquefied natural gas (LNG) pipeline. The flowing LNG could maintain the operating temperature of the inner HTS power cable within the range of 85 K-90 K, thus the Bi-2223 superconductors in the HTS power cable produce little Joule loss with the transmission current below the critical current. Owing to the advantages of high power density, low transmission losses and economical manufacturing costs, the hybrid energy transmission pipeline is expected to be widely utilized in the near future. In order to ensure the safety of the HTS power cable and explosive LNG in case of short-circuit faults, this paper tests and analyzes the characteristics of Bi-2223 HTS tapes of the Type HT-CA, Type HT-SS and Type H models under short-circuit current impacts at the LNG cooling temperature (85 K-90 K). An experimental platform is designed and established for the ampacity tests of HTS tapes above LN2 cooling temperature (77 K). The AC over-current impact tests at 85 K-90 K are carried out on each sample of Bi-2223 tapes respectively, and the experimental results are analyzed and compared to evaluate their performances under different operating conditions. The results indicate that the Type HT-CA tape can withstand 50 Hz short-circuit current impact with the amplitude of 1108 A (10 times of critical current Ic ) for 100 ms at 90 K, and its resistance is the smallest of the three tested samples under similar current impacts. Therefore, the Type HT-CA Bi-2223 tape is the optimal superconductor of the HTS power cable in the hybrid energy transmission pipeline.

关键词： Bi-2223 high-temperature superconducting(HTS)tape critical current hybrid energy transmission pipeline liquefied natural gas(LNG)cooling temperature short-circuit current impact characteristics

Flocking of a Cucker–Smale Type Model with Compactly Supported Interaction Functions

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2285-2296页

作者： Chun yin JIN Shuang Zhi li College of Science China Agricultural UniversityBeijing 100083P.R.China

How to analyze flocking behaviors of a multi-agent system with local interaction functions is a challenging problem in *** and Tadmor in 2011 also stressed the significance to assume that the interaction function is rapidly decaying or cut-off at a finite distance(*** and Tadmor in ***.2011).In this paper,we study the flocking behavior of a Cucker–Smale type model with compactly supported interaction *** properties of a connected stochastic matrix,together with an elaborate analysis on perturbations of a linearized system,we obtain a sufficient condition imposed only on model parameters and initial data to guarantee ***,it is shown that the system achieves flocking at an exponential rate.

关键词： Cucker-Smale model local interaction flocking stochastic matrix neighbor graph

Alternative Method of Constructing Granular Neural Networks

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Computers, Materials & Continua 2024年第4期79卷 623-650页

作者： Yushan yin Witold Pedrycz Zhiwu li School of Electro-Mechanical Engineering Xidian UniversityXi’an710071China Department of Electrical and Computer Engineering University of AlbertaEdmontonABT6R 2V4Canada

Utilizing granular computing to enhance artificial neural network architecture, a newtype of network emerges—thegranular neural network (GNN). GNNs offer distinct advantages over their traditional counterparts: The ability toprocess both numerical and granular data, leading to improved interpretability. This paper proposes a novel designmethod for constructing GNNs, drawing inspiration from existing interval-valued neural networks built uponNNNs. However, unlike the proposed algorithm in this work, which employs interval values or triangular fuzzynumbers for connections, existing methods rely on a pre-defined numerical network. This new method utilizesa uniform distribution of information granularity to granulate connections with unknown parameters, resultingin independent GNN structures. To quantify the granularity output of the network, the product of two commonperformance indices is adopted: The coverage of numerical data and the specificity of information *** this combined performance index helps determine the optimal parameters for the network. Finally,the paper presents the complete model construction and validates its feasibility through experiments on datasetsfrom the UCIMachine Learning Repository. The results demonstrate the proposed algorithm’s effectiveness andpromising performance.

关键词： Granular neural network granular connection interval analysis triangular fuzzy numbers particle swarm optimization(PSO)