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On the Residual Finiteness of a Class of Infinite Soluble Groups

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Algebra Colloquium 2023年第1期30卷 155-164页

作者： Jun Liao Heguo Liu xiaoliang Luo Xingzhong xu School of Mathematics and Statistics Hubei UniversityWuhan 430062China Department of Mathematics Hainan UniversityHaikou 570228China Department of Mathematics Taiyuan Normal University JinzhongShanxi 031609China

Let A be a completely decomposable homogeneous torsion-free abelian group of rank n(n≥2).Let m(n)=A×(a)be the split extension of A by an automorphismαwhich is a cyclic permutation of the direct components twisted by a rational integer m.Then Om(n)is an infinite soluble group.In this paper,the residual finiteness of Om(n)is investigated.

关键词： residual finiteness infinite soluble group nilpotent group polycyclic group

Image recognition and empirical application of desert plant species based on convolutional neural network

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Journal of Arid Land 2022年第12期14卷 1440-1455页

作者： LI Jicai SUN Shiding JIANG Haoran TIAN Yingjie xu xiaoliang School of Economics and Management University of Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Big Data Mining and Knowledge Management Chinese Academy of SciencesBeijing 100190China Research Center on Fictitious Economy and Data Science Chinese Academy of SciencesBeijing 100190China Xinjiang Institute of Ecology and Geography Chinese Academy of SciencesUrumqi 830011China

In recent years,deep convolution neural network has exhibited excellent performance in computer vision and has a far-reaching impact.Traditional plant taxonomic identification requires high expertise,which is time-consuming.Most nature reserves have problems such as incomplete species surveys,inaccurate taxonomic identification,and untimely updating of status data.Simple and accurate recognition of plant images can be achieved by applying convolutional neural network technology to explore the best network model.Taking 24 typical desert plant species that are widely distributed in the nature reserves in Xinjiang Uygur Autonomous Region of China as the research objects,this study established an image database and select the optimal network model for the image recognition of desert plant species to provide decision support for fine management in the nature reserves in Xinjiang,such as species investigation and monitoring,by using deep learning.Since desert plant species were not included in the public dataset,the images used in this study were mainly obtained through field shooting and downloaded from the Plant Photo Bank of China(PPBC).After the sorting process and statistical analysis,a total of 2331 plant images were finally collected(2071 images from field collection and 260 images from the PPBC),including 24 plant species belonging to 14 families and 22 genera.A large number of numerical experiments were also carried out to compare a series of 37 convolutional neural network models with good performance,from different perspectives,to find the optimal network model that is most suitable for the image recognition of desert plant species in Xinjiang.The results revealed 24 models with a recognition Accuracy,of greater than 70.000%.Among which,Residual Network X_8GF(RegNetX_8GF)performs the best,with Accuracy,Precision,Recall,and F1(which refers to the harmonic mean of the Precision and Recall values)values of 78.33%,77.65%,69.55%,and 71.26%,respectively.Considering the demand factors of hardware equipment and infe

关键词： desert plants image recognition deep learning convolutional neural network Residual Network X_8GF(RegNetX_8GF) Mobile Network V2(MobileNetV2) nature reserves

Atomically Thin 2D TiO_(2) Nanosheets with Ligand Modified Surface for Ultra-sensitive Humidity Sensor

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Chinese Journal of Structural Chemistry 2022年第4期41卷 54-60页

作者： Jianze Xiao Zhihua Fu Guane Wang xiaoliang Ye Gang xu College of Chemistry Fuzhou UniversityFuzhou 350116China State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of ScienceFuzhou 350002China University of Chinese Academy of Sciences Beijing 100049China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China

As a kind of two-dimensional(2D)nanostructured materials,metal oxide nanosheets(MONS)are attractive and promising humidity sensing materials due to their considerable surface area,good charge carrier transportation,and designable surface functional groups properties.Nevertheless,the ultra-thin MONS modified with active functional groups for humidity sensing are still rare.As a proof of concept,the atomically thin TiO_(2)nanosheets with high surface area and electron-donating amino groups are prepared by a structure-maintained post-ligand modification strategy.The fabricated TiO_(2)-based sensors demonstrate superior humidity sensing performance with high response,short response time,narrow hysteresis,and ultra-low theoretical limit of detection of about 15 ppm.Additionally,the possible mechanism is proposed from the AC complex impedance measurements and DC instantaneous reverse polarity experiments.This work provides a possible path for developing the high-performance 2D nanostructured metal oxides-based humidity materials through the surface chemical method.

关键词： TiO_(2)nanosheet ligand modification ultra-sensitive chemiresistive humidity sensing

Enhancement in boiling heat transfer performance using reduced graphene oxide coating with controllable components and porous structures

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Science China(Technological Sciences) 2023年第7期66卷 2080-2092页

作者： xu ZhiMing WANG xiaoliang JIANG HongPeng ZHANG ZhiRong SHAN DeBin GUO Bin QIU YunFeng xu Jie Key Laboratory of Micro-Systems and Micro-Structures Manufacturing of Ministry of Education Harbin Institute of TechnologyHarbin 150080China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China School of Medicine and Health Harbin Institute of TechnologyHarbin 150080China School of Chemistry and Chemical Engineering Yancheng Institute of TechnologyYancheng 224051China

Enhancement in boiling heat transfer performance is significant for addressing thermal management bottlenecks of advanced electronic systems.Reduced graphene oxides(rGO)are regarded as promising candidates for thermal management due to their excellent thermal properties,chemical stability and adjustable wettability.In this study,rGO coatings with micron pores and controllable oxygen contents are prepared on Al substrate via cathodic electrophoretic deposition and subsequent thermal annealing,leading to enhanced pool boiling performance.The heat transfer coefficient for Al/rGO450is 37.2 kW m-2K-1,which is increased by 112.6%compared with bare Al,also outperformed previously reported Al based substrates.It is assumed that the hydrophilic and aerophobic r GO coatings effectively promote the liquid infiltration and bubble departure during pool boiling process.Importantly,repeatability tests indicate the durable stability of vertically oriented rGO nanosheets.Reverse nonequilibrium molecular dynamics simulation indicates that the interfacial transmission coefficients of Al/rGO increase after thermal annealing,indicative of the enhanced heat transfer performance of heterogeneous interface.Our study opens a new avenue for endowing metal substrates with high pool boiling performance using porous carbon coating nanoengineering strategy with controllable morphology and components.

关键词： graphene cathodic electrophoretic deposition boiling heat transfer thermal reduction interfacial nanoengineering

Robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft with actuator saturation

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Chinese Journal of Aeronautics 2018年第6期31卷 1298-1310页

作者： xiaoliang WANG Changle XIANG Homayoun NAJJARAN Bin xu Vehicle Research Center School of Mechanical Engineering Beijing Institute of Technology Okanagan School of Engineering The University of British Columbia

This paper is concerned with the robust adaptive fault-tolerant control of a tandem coaxial ducted fan aircraft under system uncertainty, mismatched disturbance, and actuator saturation.For the proposed aircraft, comprehensive controllability analysis is performed to evaluate the controllability of each state as well as the margin to reject mismatched disturbance without any knowledge of the controller. Mismatched disturbance attenuation is ensured through a structured Hinfinity controller tuned by a non-smooth optimization algorithm. Embedded with the H-infinity controller, an adaptive control law is proposed in order to mitigate matched system uncertainty and actuator fault. Input saturation is also considered by the modified reference model. Numerical simulation of the novel ducted fan aircraft is provided to illustrate the effectiveness of the proposed method. The simulation results reveal that the proposed adaptive controller achieves better transient response and more robust performance than classic Model Reference Adaptive Control（MRAC） method, even with serious actuator saturation.

关键词： Comprehensive controllability Ducted fan aircraft Fault-tolerant Input saturation Robust adaptive control

Potassium 2-(1-hydroxypentyl)-benzoate improves depressive-like behaviors in rat model

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Acta Pharmaceutica Sinica B 2018年第6期8卷 881-888页

作者： Hao Ma Weiping Wang Shaofeng xu Ling Wang xiaoliang Wang State Key Laboratory of Bioactive Substances and Functions of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College

Potassium 2-(1-hydroxypentyl)-benzoate(PHPB) is a novel drug candidate for acute ischemic stroke. PHPB has been also shown to be beneficial for some neurodegenerative diseases. In this study, we demonstrated that PHPB improved depressive-like behaviors induced by chronic unpredictable mild stress(CUMS) in rats. Male SD rats were subjected to the stress for five weeks. PHPB(30 and 100 mg/kg) or fluoxetine(FLX 10 mg/kg, as positive control) was administered orally from the third week in CUMS procedure. The behavioral tests were applied and then the biochemical studies were carried out. PHPB or FLX treatment rescued the behavioral deficiency in CUMS-exposed rats. Meanwhile, PHPB normalized the enhanced level of serum corticosterone, improved hippocampal and serum BDNF levels, as well as p-CREB level in hippocampus. In addition, PHPB could reverse the reduced level of extracellular 5-HT and its metabolite 5-HIAA in prefrontal cortex(PFC) of depressed rats. In summary, our results showed that PHPB improved depression-like behaviors in CUMS-exposed rats. The mechanisms might relate to the reverse of neurotrophic disturbance in the brain, reducing excessive HPA axis response and facilitating the release of 5-HT.

关键词： PHPB CUMS Antidepressant BDNF HPA axis 5-HT

Proliferation-mediated asymmetric nanoencapsulation of singlecell and motility differentiation

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Science China(Technological Sciences) 2023年第7期66卷 2134-2146页

作者： WANG ShengLiang xu ZhiJun CHEN Haixu WANG xiaoliang LIN Song WANG Lei LIU XiaoMan HUANG Xin MIIT Key Laboratory of Critical Materials Technology for New Energy Conversion and Storage School of Chemistry and Chemical EngineeringHarbin Institute of TechnologyHarbin 150001China

The biointerface engineering of living cells by creating an abiotic shell has important implications for endowing cells with exogenous properties with improved cellular behavior,which then boosts the development of the emerging field of living cell hybrid materials.Herein,we develop a way to perform active nanoencapsulation of single cell,which then endows the encapsulated cells with motion ability that they do not inherently possess.The emerging motion characteristics of the encapsulated cells could be self-regulated in terms of both the motion velocity and orbits by different proliferation modes.Accordingly,by taking advantage of the emergence of differentiated moving abilities,we achieve the self-sorting between mother cells and daughter cells in a proliferated Saccharomyces cerevisiae cell community.Therefore,it is anticipated that our highlighted study could not only serve as a new technique in the field of single-cell biology analysis and sorting such as in studying the aging process in Saccharomyces cerevisiae,but also open up opportunities to manipulate cell functionality by creating biohybrid materials to fill the gap between biological systems and engineering abiotic materials.

关键词： biointerface engineering micromotors self-propulsion self-sorting urease

Improvement of multi-functional properties by fabricating micro-pillar arrays structures on zirconium alloy surface

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Science China(Technological Sciences) 2022年第6期65卷 1243-1252页

作者： WANG xiaoliang WANG HaoYu LIU YongDa QI Min REN QuanYao xu Jie SHAN DeBin GUO Bin Key Laboratory of Micro-systems and Micro-structures Manufacturing of Ministry of Education Harbin Institute of TechnologyHarbin 150080China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Science and Technology on Reactor System Design Technology Laboratory Chengdu 610041China

Although using the microstructure of a surface to enhance specific functions has immense applicability in numerous fields,few studies have been conducted on the multi-functional properties of nuclear fuel elements in harsh environments.In this study,surfaces with zirconium alloy micro-pillar arrays were prepared using micro-milling and ultraviolet nanosecond laser technology,and their functional properties such as the wettability,structural stability,and corrosion resistance were investigated.It was found that the geometric dimension of the micro-pillar arrays prepared using these two methods could meet the design requirements,but the micro-milling process had the best dimensional accuracy.Micro-nano multi-scale structures were obtained by laser ablation.However,these multi-scale structures exhibited weak structural stability,and the nanostructures were easily corroded.By contrast,the micro-pillar arrays manufactured using micro-milling were confirmed to have better structural stability and corrosion resistance.On one hand,the area mass loss of the micro-milled structure was lower than that of a flat surface after experiencing high-pressure fluid scouring at 8 and 38 m/s.On the other hand,the oxidation weight gain of the surface with the micro-milled structure was lower than that of a flat surface,and the oxide film was 22.5% thinner after 100 days of deionized water corrosion at 360℃ and 18.7 MPa.

关键词： zirconium alloy micro-pillar arrays wettability structural stability corrosion

Winding Function Theory Based Thrust Calculation on Nested-loop Secondary Linear Machine Adapted to Linear Metro

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CES Transactions on Electrical Machines and Systems 2023年第2期7卷 153-162页

作者： Yaping Zhang Jian Ge Wei xu Hao Tang Yang Gao xiaoliang Chen Shihu Su Zhen Bao the State Key Laboratory of Advanced Electromagnetic Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China IEEE Xiangyang CRRC Motor Technology Co. Ltd.Xiangyang 441000China CRRC Zhuzhou Institute Co. Ltd.Zhuzhou 412001China Guangzhou Metro Group Co. Ltd.Guangzhou 510330China the Zhuzhou CRRC Times Electric Co. Ltd.and CRRC Zhuzhou Motor Co.Ltd.Zhuzhou 412001China

With advantages of strong drive capability,nested-loop secondary linear machine(NLS-LM)has great potentiality in linear metro.For its secondary structure with multiple loops,it is difficult to calculate the electromagnetic thrust of NLS-LM reasonably.Hence,in this paper,one thrust calculation method is proposed considering variable loop inductance and transient loop current.Firstly,to establish the secondary winding function,the modeling domain is confined to a limited range,and the equivalent loop span is employed by analyzing the coupling relationship between primary and secondary.Then,in order to obtain the secondary flux density,the transient secondary current is solved based on the loop impedance and induced voltage.Finally,the electromagnetic thrust can be calculated reasonably by the given primary current sheet and the calculated secondary flux density.Comprehensive simulations and experiments have demonstrated the effectiveness of the proposed method.

关键词： Nested-loop secondary Linear metro Electro-magnetic thrust Finite element algorithm(FEA) Transient nested-loop current Winding function