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Optoelectronics Letters 2025年第3期21卷 149-154页

作者： li wenqiang WU Min li Weijun HAO Meilan YU lina Ann Lab Institute of Semiconductors Chinese Academy of Sciences School of Electronic Electrical and Communication Engineering & School of Integrated Circuits University of Chinese Academy of Sciences Beijing Key Laboratory of Semiconductor Neural Network Intelligent Sensing and Computing Technology

In recent years, machine learning (ML) techniques have been shown to be effective in accelerating the development process of optoelectronic devices. However, as"black box"models, they have limited theoretical interpretability. In this work, we leverage symbolic regression (SR) technique for discovering the explicit symbolic relationship between the structure of the optoelectronic Fabry-Perot (FP) laser and its optical field distribution, which greatly improves model transparency compared to ML. We demonstrated that the expressions explored through SR exhibit lower errors on the test set compared to ML models, which suggests that the expressions have better fitting and generalization capabilities.

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Engineered microorganisms and enzymes for efficiently synthesizing plant natural products

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Chinese Journal of Chemical Engineering 2021年第2期34卷 62-73页

作者： wenqiang li Wentao Sun Chun li Key Lab for Industrial Biocatalysis Ministry of EducationDepartment of Chemical EngineeringTsinghua UniversityBeijing 100084China

Plant natural products are a kind of active substance widely used in pharmaceuticals and ***,the current production mode based on plant culture and extraction suffer complex processes and severe concerns for environmental and *** the increasing awareness of environmental sustainability,engineered microbial cell factories have been an alternative approach to produce natural *** engineering strategies have been utilized in microbial biosynthesis of complex phytochemicals such as dynamic control and substructure ***,Enzyme engineering including directed evolution and rational design has been implemented to improve enzyme catalysis efficiency and stability as well as change promiscuity to expand product *** this review,we discussed recent advances in microbial biosynthesis of complex phytochemicals from the following aspects,including pathway construction,strain engineering to boost the production.

关键词： Plant natural products Microorganisms Synthetic biology Enzyme engineering

Strain gradient induced grain refinement far below the size limit in a low carbon hypoeutectoid steel(0.19 wt%C)via pipe inner surface grinding treatment

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Journal of Materials Science & Technology 2021年第19期78卷 155-169页

作者： wenqiang li Yiming Zhao Ning liu Changji li Ruiming Ren Dayong Cai Hongwang Zhang National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao 066004China National Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China liren College of Yanshan University Yanshan UniversityQinhuangdao 066004China School of Materials Science&Engineering Dalian Jiaotong UniversityDalian 116028China Qinhuangdao Vocational and Technical College Qinhuangdao 066100China

A low carbon hypoeutectoid steel(0.19 wt%C)with proeutectoid ferrite and pearlite dual-components was subjected to surface plastic deformation via pipe inner surface grinding(PISG)at room *** deformation microstructures for each component were systematically characterized along depth,and the patterns of structural evolution toward nanometer regime as well as the governing parameters were *** ferrite grains were refined down to 17 nm,and the pattern covering a length scale of 4–5 orders of magnitude from micron-to nanometer-scale follows:formation of cellular dislocation structure(CDS),elongated dislocation structure(EDS),ultrafine lamellar structure(UFL)and finally the nanolaminated structure(NL).The pearlite experiences the deformation and refinement,and finally the transforming the ultrafine pearlite(UFP)into nanolaminated pearlite(NLP)with the ferrite lamellae as thin as 20 *** for both UFL(UFP)and NL(NLP)can be realized via forming novel extended boundaries within ferrite lamellae.A critical lattice curvature of~2.8°is required for forming such extended boundary,corresponding to a minimum strain gradient of 0.25μm^(-1)for a 100 nm-thick *** below size limit(expressed by lamellar thickness d_Tin nm)is correlated with the strain gradient(χ,inμm^(-1))by:d_T=12.5/*** contributions from strain gradient caused by PISG processing and material heterogeneity were discussed.

关键词： Strain gradient Grain refinement Size limit Low carbon hypoeutectoid steel Pipe inner surface grinding

Backward linear quadratic stochastic optimal control problems and nonzero sum differential games

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Backward linear quadratic stochastic optimal control problem...

Research and Application of a Multi-Field Co-Simulation Data Extraction Method Based on Adaptive Infinitesimal Element

第25届中国控制与决策会议

作者： Yanjun Lou wenqiang li School of Mathematics and Statistics Shandong University at Weihai

ISBN: (纸本)9781467355339

In R. Buckdahn, li, Peng [6], the authors obtained mean-field backward stochastic Differential equations （BSDEs） in a natural way as a limit of some highly dimensional system of forward and backward SDEs, corresponding to a great number of particles. In this paper, firstly, we prove that there exists a unique solution of fully coupled MF-FBSDE. Then we use the solutions of mean-field forward-backward stochastic differential equations to get the explicit form of the optimal control for linear quadratic optimal control problem and the open-loop Nash equilibrium point of nonzero sum differential games.

关键词： Mean-field forward-backward stochastic differential equations stochastic optimal control nonzero sum differential games.

来源： cnki会议评论

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Computer Modeling in Engineering & Sciences 2024年第1期138卷 321-348页

作者： Changfu Wan wenqiang li Sitong ling Yingdong liu Jiahao Chen School of Mechanical Engineering Sichuan UniversityChengdu610065China Innovation Method and Creative Design Key Laboratory of Sichuan Province Sichuan UniversityChengdu610065China

Regarding the spatial profile extraction method of a multi-field co-simulation dataset,different extraction directions,locations,and numbers of profileswill greatly affect the representativeness and integrity of *** this study,a multi-field co-simulation data extractionmethod based on adaptive infinitesimal elements is *** co-simulation dataset based on related infinitesimal elements is constructed,and the candidate directions of data profile extraction undergo dimension reduction by principal component analysis to determine the direction of data *** on the fireworks algorithm,the data profile with optimal representativeness is searched adaptively in different data extraction intervals to realize the adaptive calculation of data extraction micro-step *** multi-field co-simulation data extraction process based on adaptive microelement is established and applied to the data extraction process of the multi-field co-simulation dataset of the sintering *** with traditional data extraction methods for multi-field co-simulation,the approximate model constructed by the data extracted from the proposed method has higher construction ***,the relative maximum absolute error,root mean square error,and coefficient of determination of the approximationmodel are better than those of the approximation model constructed by the data extracted from traditional methods,indicating higher accuracy,it is verified that the proposed method demonstrates sound adaptability and extraction efficiency.

关键词： Multi-field co-simulation adaptive infinitesimal elements principal component analysis fireworks algorithm sintering furnace simulation

Reactive ball-milling synthesis of Co-Fe bimetallic catalyst for efficient hydrogenation of carbon dioxide to value-added hydrocarbons

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Journal of Energy Chemistry 2023年第9期84卷 210-218页

作者： Haipeng Chen Chenwei Wang Mengyang Zheng Chenlei liu wenqiang li Qingfeng Yang Shixue Zhou Xun Feng College of Chemistry and Chemical Engineering Henan Key Laboratory of Function-Oriented Porous MaterialsLuoyang Normal UniversityLuoyang 471934HenanChina State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021NingxiaChina College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao 266590ShandongChina

Catalytic hydrogenation of CO_(2) using renewable hydrogen not only reduces greenhouse gas emissions,but also provides industrial ***,a Co-Fe bimetallic catalyst was developed by a facile reactive ball-milling method for highly active and selective hydrogenation of CO_(2) to value-added *** reacted at 320℃,1.0 MPa and 9600 mL h^(-1) g_(cat)^(-1),the selectivity to light olefin(C_(2)^(=)-C_(4)^(=)) and C_(5)+ species achieves 57.3% and 22.3%,respectively,at a CO_(2) co nversion of 31.4%,which is superior to previous Fe-based *** CO_(2) activation can be promoted by the CoFe phase formed by reactive ball milling of the Fe-Co_(3)O_(4) mixture,and the in-situ Co_(2)C and Fe_(5)C_(2) formed during hydrogenation are beneficial for the C-C coupling *** initial C-C coupling is related to the combination of CO species with the surface carbon of Fe/Co carbides,and the sustained C-C coupling is maintained by self-recovery of defective *** new strategy contributes to the development of efficient catalysts for the hydrogenation of CO_(2) to value-added hydrocarbons.

关键词： Reactive ball milling Co-Fe bimetallic catalyst Carbon dioxide Value-added hydrocarbon C–C coupling reaction

Construction of physical crosslink-based chitosan/liquid crystal composite hydrogel and evaluation on their cytocompatibility

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Regenerative Biomaterials 2017年第1期4卷 39-45页

作者： lin Du Xiaohui Yang wenqiang li Xuhui Luo Hao Wu Jiaqing Zhang Mei Tu Department of Materials Science and Engineering Jinan UniversityGuangzhou 510632People’s Republic of China Engineering Research Center of Artificial Organs and Materials Ministry of EducationJinan UniversityGuangzhou 510632People’s Republic of China The First Affiliated Hospital Jinan UniversityGuangzhou 510632People’s Republic of China School of Medicine Jinan UniversityGuangzhou 510632People’s Republic of China

In order to provide a novel biomimetic composite substrate for tissue engineering and explore the interaction between cells and this type of material,we developed chitosan/liquid crystal(CS/LC)composite hydrogel with embedded LC phases by composing of cholesterol hydroxypropyl cellulose ester liquid crystalline material and *** micromorphology of CS/LC composite hydrogels exhibited‘islands-sea’phase separation structures similar to the‘fluid mosaic model’of *** vitro cell compatibility study suggested that 3T3 is fibroblasts exhibited better initial cell adhesions and higher proliferation rates on the composite hydrogel than on the polystyrene control plate and the pure LC *** novel CS/LC composite hydrogel provides more favorable interface for cell growth and proliferation and may serve as potentially active substrate for engineering interfaces to live cells.

关键词： chitosan liquid crystal composite hydrogels structure and morphology cell compatibility

Dual-band reflective polarization converter based on metasurface

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Optoelectronics Letters 2023年第12期19卷 716-720页

作者： liN Xiaofang ZHANG Xu CHANG Ming li wenqiang YU Siyang ZHANG Maolong Air Force Communications NCO Academy Dalian I16000China Shandong Provincial Key Laboratory of Laser Polarization and Information Technology School of Physics and Physical EngineeringQufu Normal UniversityQufu 273165China Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology Shanghai 200092China

In this paper,a dual-band and reflective polarization converter based on metasurface is *** unit cell is composed of two layers of metal plates separated by a dielectric *** simulation results show that the proposed converter is able to convert x-or y-polarized incident waves into cross-polarized waves perfectly in frequency bands of 6.75–10.59 GHz and 17.78–19.61 GHz,and the polarization conversion ratio(PCR)is nearly 100%,which can also convert linearly polarized waves into circularly polarized waves at four *** can be widely used in applications of radar satellites,antenna design and telecommunication with the function of realizing polarization conversion in two bands and achieving high PCR simultaneously.

关键词： polarization reflective converter

Modified NiFe-MOF with defects induced by-NH_(2)and-SH for enhanced adsorption and photocatalytic reduction of CO_(2)

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Journal of Materials Science & Technology 2024年第3期170卷 167-176页

作者： Ruting Huang Yeyin Zhang wenqiang li Wanxia Zhang Yong Fang Wenrui Zhang Anqi Cui Yu Ying Xianyang Shi Information Materials and Intelligent Sensing Laboratory of Anhui Province Anhui Province Key Laboratory of Wetland Ecosystem Protection and RestorationSchool of Resource and Environmental EngineeringAnhui UniversityHefei230601China Key Laboratory of Nutrient Cycling Resources and Environment of Anhui Institute of Soil and FertilizerAnhui Academy of Agricultural SciencesHefei230001China

In this study,a Ni-Fe metal-organic framework modified by-NH_(2)and-SH was synthesized using a sim-ple hydrothermal process for enhancing photocatalytic CO_(2)*** expected,the N2S-NiFe(NH_(2)-BDC/H_(4)DSBDC,2:1)displayed excellent photocatalytic CO_(2)reduction activity and high CO selectivity(12,412.23μmol g^(−1)h^(−1))under visible light irradiation(λ≥420 nm),which is 5 times that of ***,the excellent photocatalytic performance of N2S-NiFe can benefit from the rich defect trap site caused by the introduction of amino and sulfhydryl groups,accelerating charge transfer and promoting space charge separation,as supported by the photo-electrochemical *** better understand the CO_(2)adsorption mechanism,density functional theory calculations were performed,which revealed that the Niov site has more negative adsorption energy compared with the Feov *** study provides a simple strategy to establish efficient photocatalysts for CO_(2)reduction through the modification of organic ligands.

关键词： NiFe-MOF CO_(2)reduction Defect structure Photocatalytic

Photon counting technique as a potential tool in micro-defect detection of epoxy insulation pull rod in gas-insulated switchgears

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High Voltage 2024年第2期9卷 267-274页

作者： Xianhao Fan Shu Niu Hanhua Luo Jizhong liang Fang liu wenqiang li Weidong liu Wensheng Gao Yulong Huang Chuanyang li Jinliang He School of Electrical Engineering Tsinghua UniversityBeijingChina Electric Power Research Institute Shangxi Power Grid CorporationTaiyuanShanxiChina Shandong Taikai Electrical Insulation Co. Ltd.TaianShandongChina

The micro-defects in epoxy-based insulation materials generate a local high electric field which results in continuous degradation,seriously endangering the insulation system of gas-insulated switchgears.A highly sensitive detection technique is reported for micro-defects of insulation pull rods based on the photon counting(PC)*** re-sults demonstrated that for an epoxy-based insulation pull rod,the photons released during electroluminescence and ionisation at 2 kV,which is less than the partial discharge inception voltage,can be clearly *** findings presented a strong correlation between photon counts and defect *** has been conducted to elucidate the mechanism behind defect-induced PC,employing the amplification of ionising luminescence through electric field distortion induced by micro defects and the augmentation of electroluminescence through the aggregation of trap *** this regard,the authors verified that PC can serve as a potential tool in the detection of micro-insulation defects,which also has huge potential in online insulation condition monitoring.

关键词： technique. insulation defect