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Miura origami based reconfigurable polarization converter for multifunctional control of electromagnetic waves

Photonics Research 2024年第3期12卷 581-586页

作者： ZHIBIAO ZHU YONGFENG LI ZHE QIN LIXIN jiang wenjie WANG HONGYA CHEN JIAFU WANG YONGQIANG PANG SHAOBO QU Shaanxi Key Laboratory of Artificially-Structured Functional Materials and Devices Air Force Engineering UniversityXi’an 710051China School of Electronic Science and Engineering Xi’an Jiaotong UniversityXi’an 710049China

Polarization is one of the basic characteristics of electromagnetic(EM)waves,and its flexible control is very important in many practical applications.At present,most of the multifunction polarization metasurfaces are electrically tunable based on PIN and varactor diodes,which are easy to operate and have strong real-time performance.However,there are still some problems in them,such as few degrees of freedom of planar structure control,complex circuit,bulky sample,and high cost.In view of these shortcomings,this paper proposes a Miura origami based reconfigurable polarization conversion metasurface for multifunctional control of EM waves.The interaction between the electric dipoles is changed by adjusting the folding angleθ,thereby tuning the operating frequency of the polarization conversion and the polarization state of the reflected wave.This mechanical control method brings more degrees of freedom to manipulate EM waves.And the processed sample is with lightweight and low cost.To verify the performance of the proposed origami polarization converter,a Miura origami structure loaded with metal split rings is designed and fabricated.The operating frequency of the structure can be tuned in different folding states.In addition,by controlling the folding angleθ,linear-to-linear and linear-to-circular polarization converters can be realized at different folding states.The proposed Miura origami polarization conversion metasurface provides a new idea for reconfigurable linear polarization conversion and multifunctional devices.

关键词： polarization reconfigurable tuning

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An Improved JSO and Its Application in Spreader Optimization of Large Span Corridor Bridge

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Computer Modeling in Engineering & Sciences 2024年第3期138卷 2357-2382页

作者： Shude Fu Xinye Wu wenjie Wang Yixin Hu Zhengke Li Feng jiang Fujian Key Laboratory of Digital Simulations for Coastal Civil Engineering School of Architecture and Civil EngineeringXiamen UniversityXiamen361005China Xiamen Transportation Infrastructure Intelligent Management and Maintenance Engineering Technology Research Center Xiamen361005China Fuzhou Company of China Communications Construction Co. Ltd.Fuzhou350005China

In this paper,given the shortcomings of jellyfish search algorithmwith low search ability in the early stage and easy to fall into local optimal solution,this paper introduces adaptive weight function and elite strategy,improving the global search scope in the early stage and the ability to refine the local development in the later stage.In the numerical study,the benchmark problem of dimensional optimization with a 10-bar truss structure and simultaneous dimensional shape optimization with a 15-bar truss structure is adopted,and the corresponding penalty method is used for constraint treatment.The test results show that the improved jellyfish search algorithm can provide better truss sections as well as weights.Because when the steel main truss of the large-span covered bridge is lifted,the site is limited and the large lifting equipment cannot enter the site,and the original structure does not meet the problem of stress concentration and large deformation of the bolt group,so the spreader is used to lift,and the improved jellyfish search algorithm is introduced into the design optimization of the spreader.The results show that the improved jellyfish algorithm can efficiently and accurately find out the optimal shape and weight of the spreader,and throughMidas Civil simulation,the spreader used canmeet the requirements of weight and safety.

关键词： Truss optimization improved JSO size optimization shape optimization

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Sealing performance and mechanical response of mud pump piston

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Petroleum 2023年第1期9卷 101-107页

作者： Jie Zhang wenjie jiang Pai Zhu Ting Zheng School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500China Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan Province Chengdu610500China Luzhou Vocational and Technical College Luzhou646000China

In order to explore the effect of piston cup structure on its sealing characteristics and mechanical properties,a numerical simulation model of the piston cup in the BW-160 mud pump was established.Effects of work load,friction coefficient and cup structure parameters on the sealing and mechanical properties of the piston were discussed under mud discharge condition.The results show that stress concentration on the root and lips of the cup is becoming more and more obvious with the working load increases.The average contact pressure increases with the friction coefficient increases,but an excessive friction coefficient accelerate the wear of the cup and the heat generation.Effect of the piston lip interference and thickness on the sealing performance of the cup is greater than that of the inner wall width.The piston with groove structure can effectively improve the sealing performance of the piston.The mechanical properties of triangular groove cup are better than that of semicircular and trapezoidal groove cup.

关键词： Piston cup Sealing performance Mechanical property Groove structure

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2,000,000 fps 2D and 3D imaging of periodic or reproducible scenes with single-pixel detectors

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Photonics Research 2022年第9期10卷 2157-2164页

作者： wenjie jiang YONGKAI YIN JUNPENG JIAO XIAN ZHAO BAOQING SUN School of Information Science and Engineering Shandong UniversityQingdao 266237China Key Laboratory of Laser&Infrared System Ministry of EducationQingdao 266237China Center for Optics Research and Engineering Shandong UniversityQingdao 266237China

Single-pixel imaging(SPI)can capture 2D images of the target with only a nonpixelated detector,showing promising application potential in nonvisible spectral imaging,low-photon imaging,lidar,and other extreme imaging fields.However,the imaging mechanism of traditional SPI makes it difficult to achieve high imaging speed,which is a primary barrier for its widespread application.To address this issue,in this work,we propose and demonstrate a novel high-speed 2D and 3D imaging scheme based on traditional SPI,termed time-resolved single-pixel imaging(TRSPI).Previous SPI works mainly utilize correlation between a stable target and iterative illumination masks to reconstruct a single image.In TRSPI,by further exploiting correlation information between a dynamic scene and every static mask,we can reconstruct a series of time-varying images of the dynamic scene,given the dynamic scene is repetitive or reproducible.Experimentally,we conducted 2D and 3D imaging on a rotating chopper with a speed of 4800 revolutions per minute(rpm),and imaging speeds up to 2,000,000 fps.It is believed that this technology not only opens up a novel application direction for SPI,but also will provide a powerful solution for high-speed imaging.

关键词： SPI utilize scene

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UltrahighQ Sr_(1+x)Y_(2)O_(4+x)(x=0-0.04)microwave dielectric ceramics for temperature-stable millimeter-wave dielectric resonator antennas

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Journal of Advanced Ceramics 2024年第2期13卷 155-165页

作者： Guoqiang He Yu jiang Kaixin Song Yanjun Liu Yuan Nie wenjie Zhang Ziqi Zhao Yinghan He Xinyue Ma Xiuli Chen Xu Li Huanfu Zhou Collaborative Innovation Centre for Exploration of Hidden Nonferrous Metal Deposits and Development of New Materials in Guangxi Key Laboratory of Nonferrous Materials and New Processing TechnologyMinistry of EducationSchool of Materials Science and EngineeringGuilin University of TechnologyGuilin 541004China College of Electronic Information Hangzhou Dianzi UniversityHangzhou 310018China

Microwave dielectric ceramics should be improved to advance mobile communication technologies further.In this study,we prepared Sr_(1+x)Y_(2)O_(4+x)(x=0-0.04)ceramics with nonstoichiometric Sr^(2+)ratios based on our previously reported SrY_(2)O_(4) microwave dielectric ceramic,which has a low dielectric constant and an ultrahigh quality factor(Q value).The ceramic exhibited a 33.6% higher Q-by-frequency(Q×f)value(Q≈12,500)at x=0.02 than SrY_(2)O_(4).All Sr_(1+x)Y_(2)O_(4+x)(x=0-0.04)ceramics exhibited pure phase structures,although variations in crystal-plane spacings were observed.The ceramics are mainly composed of Sr-O,Y1-O,and Y_(2)-O octahedra,with the temperature coefficient of the resonant frequency(τ_(f))of the ceramic increasing with Y_(2)-O octahedral distortion.The ceramic comprises uniform grains with a homogeneous elemental distribution,clear grain boundaries,and no obvious cavities at x=0.02.The Sr_(1+x)Y_(2)O_(4+x)(x=0-0.04)ceramics exhibited good microwave dielectric properties,with optimal performance observed at x=0.02(dielectric constant(εr)=15.41,Q×f=112,375 GHz,and τ_(f)=-17.44 ppm/℃).The τ_(f) value was reduced to meet the temperaturestability requirements of 5G/6G communication systems by adding CaTiO_(3),with Sr_(1.02)Y_(2)O_(4.02)+2wt% CaTiO_(3) exhibiting ε_(r)=16.14,Q×f=51,004 GHz,andτf=0 ppm/℃.A dielectric resonator antenna prepared using Sr_(1.02)Y_(2)O_(4.02)+2wt%CaTiO_(3) exhibited a central frequency of 26.6 GHz,with a corresponding gain and efficiency of 3.66 dBi and 83.14%,respectively.Consequently,Sr_(1.02)Y_(2)O_(4).02-based dielectric resonator antennas are suitable for use in 5G millimeter-wave band(24.5-27.5 GHz)applications.

关键词： millimeter wave microwave dielectric ceramics dielectric resonator antenna nonstoichiometric ratio

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Strong electronic coupling of CoNi and N-doped-carbon for efficient urea-assisted H2 production at a large current density

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Carbon Energy 2023年第12期5卷 187-199页

作者： Guangfu Qian Jinli Chen wenjie jiang Tianqi Yu Kexin Tan Shibin Yin Guangxi Key Laboratory of Electrochemical Energy Materials College of Chemistry and Chemical EngineeringCollege of Light Industry and Food EngineeringGuangxi UniversityNanningChina

Exploiting efficient urea oxidation reaction(UOR)and hydrogen evolution reaction(HER)catalysts are significant for energy-saving H2 production through urea-assisted water electrolysis,but it is still challenging.Herein,carbon-encapsulated CoNi coupled with CoNiMoO(CoNi@CN-CoNiMoO)is prepared by solvothermal method and calcination to enhance the activity/stability of urea-assisted water electrolysis at large current density.It exhibits good activity for UOR(E10/1,000=1.29/1.40 V)and HER(E-10/-1000=-45/-245 mV)in 1.0 M KOH+0.5 M urea solution.For the UOR||HER system,CoNi@CN-CoNiMoO only needs 1.58 V at 500 mA cm-2 and shows good stability.Density functional theory calculation suggests that the strong electronic interaction at the interface between NiCo alloy and N-doping-carbon layers can optimize the adsorption/desorption energy of UOR/HER intermediates and accelerate the water dissociation,which can expedite urea decomposition and Volmer step,thus increasing the UOR and HER activity,respectively.This work provides a new solution to design UOR/HER catalysts for H2 production through urea-assisted water electrolysis.

关键词： carbon-encapsulated structure catalyst hydrogen production large current density urea-assisted water electrolysis

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Therapy and mechanism of natural polysaccharides for atopic dermatitis treatment

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Food Science and Human Wellness 2024年

作者： wenjie Wang Lijun Shao Xiao jiang Qiulu Chu Jian Xiao Shufang Wu College of Light Industry and Food Engineering Nanjing Forestry University Department of Forest Biomaterials North Carolina State University jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry University

Atopic dermatitis (AD) is a common multifactorial skin disease characterized by chronic inflammation， unbearable itching， and significant physical and mental burden on patients. In recent years， there has been extensive studied on the use of natural polysaccharides in anti-inflammatory therapy， due to their low toxicity and multi-target pharmacological activity. The unique biological activities of polysaccharides from natural sources as functional food additives and cosmeceuticals present a new option for the treatment of AD. This review aims to summarize the pathogenesis of AD， the therapeutic effects， and the mechanisms of natural polysaccharides， as well as discuss the limitations and prospects of these compounds in the treatment of AD. The insights provided in this review can serve as references and inspiration for the development of applications of natural polysaccharides in the treatment of AD.

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The UDP-glycosyltransferase OsUGT706D2 positively regulates cold and submergence stress tolerance in rice

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The Crop Journal 2024年第3期12卷 732-742页

作者： Qing Liu Lanlan Zhang Shuwei Lyu Hang Yu wenjie Huang Liqun jiang Jing Zhang Bingrui Sun Xingxue Mao Pingli Chen Junlian Xing Wenfeng Chen Zhilan Fan Shijuan Yan Chen Li Guangdong Key Laboratory of New Technology in Rice Breeding/Guangdong Rice Engineering Laboratory/Key Laboratory of Genetics and Breeding of High Quality Rice in Southern China(Co-construction by Ministry and Province) Ministry of Agriculture and Rural AffairsRice Research InstituteGuangdong Academy of Agricultural SciencesGuangzhou 510640GuangdongChina Guangdong Key Laboratory for Crop Germplasm Resources Preservation and Utilization Agro-biological Gene Research CenterGuangdong Academy of Agricultural SciencesGuangzhou 510640GuangdongChina

In a genome-wide association study,we identified a rice UDP-glycosyltransferase gene,OsUGT706D2,whose transcription was activated in response to cold and submergence stress and to exogenous abscisic acid(ABA).OsUGT706D2 positively regulated the biosynthesis of tricin-4’-O-(syringyl alcohol)ether-7-O-glucoside at both the transcriptional and metabolic levels.OsUGT706D2 mediated cold and submergence tolerance by modulating the expression of stress-responsive genes as well as the abscisic acid(ABA)signaling pathway.Gain of function of OsUGT706D2 increased cold and submergence tolerance and loss of function of OsUGT706D2 reduced cold tolerance.ABA positively regulated OsUGT706D2-mediated cold tolerance but reduced submergence tolerance.These findings suggest the potential use of OsUGT706D2 for improving abiotic stress tolerance in rice.

关键词： UDP-glycosyltransferase Rice Cold tolerance Submergence tolerance ABA

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环角膜缘缝合与激光光凝模型:两种慢性高眼压模型的比较

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中南大学学报（医学版） 2024年第1期49卷 84-94页

作者：王俊李悦曾文杰姜文敏中南大学湘雅二医院眼科长沙410011 湖南省眼科研究中心长沙410011

目的:青光眼是一种多因素相关的视神经病变,致盲率高,其发病机制复杂,目前尚未明确。高眼压是目前唯一可调控的、与青光眼的发病密切相关的危险因素。本研究通过运用环角膜缘缝合与小梁网联合巩膜静脉激光光凝2种不同的方法建立慢性高... 详细信息

目的:青光眼是一种多因素相关的视神经病变,致盲率高,其发病机制复杂,目前尚未明确。高眼压是目前唯一可调控的、与青光眼的发病密切相关的危险因素。本研究通过运用环角膜缘缝合与小梁网联合巩膜静脉激光光凝2种不同的方法建立慢性高眼压大鼠模型,比较2种模型的眼压升高程度和高眼压持续时间,视网膜形态损伤和视网膜神经节细胞(retinal ganglion cells,RGCs)损伤程度,以及超微结构改变等。方法:建立2种慢性高眼压模型,分为环角膜缘缝合组(缝合组,用10/0尼龙线沿角巩膜缘缝合)和激光光凝组(激光组,激光灼烧小梁网联合巩膜外静脉),并以其对侧眼作为对照组。观察并定期规律监测2组大鼠的眼压变化。采用大鼠视网膜切片HE染色观察2种慢性高眼压模型对视网膜和视神经病理学的影响,透射电镜(transmission electron microscope,TEM)观察慢性高眼压模型超微结构中线粒体形态的变化,大鼠视网膜铺片Brn3b抗体免疫荧光染色特异性标记RGCs并计数,蛋白质印迹法检测凋亡相关蛋白caspase-3的表达以明确RGCs的凋亡情况。结果:与对照组相比,缝合组与激光组大鼠眼压均明显升高(均P<0.05),其中缝合组的眼压最高升高1.5倍,眼压显著升高持续8周;激光组的眼压最高达对照组的2倍,持续12周。2组都会导致RGCs丢失,与Brn3b染色的结果相符,2组caspase-3表达水平均升高(均P<0.05)。而在TEM下,2组RGCs中的线粒体形态均变为碎片化,从正常的长条形变小、变圆。与激光组相比,缝合组视网膜形态学的病理变化较轻微。结论:环角膜缘缝合可建立有效的慢性高眼压模型,诱导与激光光凝模型相似的青光眼性病理改变,但病理改变较激光光凝轻微。相较于激光光凝建模,环角膜缘缝合法对于设备要求和操作能力要求更低。

关键词：青光眼模型慢性高眼压视网膜神经节细胞凋亡线粒体功能障碍大鼠

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基于光伏无功调节的配电网电压控制策略研究

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电气传动自动化 2024年第2期46卷 24-27页

作者：蒋雯洁国网台州供电公司浙江台州318000

随着新能源发电技术的飞速发展,光伏发电系统正在大规模接入到配电网中,但是配电网电压控制是一个难题。本文基于光伏发电系统无功调节,提出了一种新型的配电网电压控制策略,设定电压报警区间,当电压达到报警区间并且存在超越报警限值... 详细信息

随着新能源发电技术的飞速发展,光伏发电系统正在大规模接入到配电网中,但是配电网电压控制是一个难题。本文基于光伏发电系统无功调节,提出了一种新型的配电网电压控制策略,设定电压报警区间,当电压达到报警区间并且存在超越报警限值的趋势时进行电压控制,从而保证将电压控制在合理的区间内,通过电压调节系数和电压成本系数来确定调节顺序和调节方法。在仿真环境下构建仿真模型,将本文提出的控制策略与其他控制策略进行对比研究,本文提出的控制策略能够更有效地提高电压质量,实现调压成本的科学控制,具备一定的优越性,可以进行大规模推广应用。

关键词：光伏发电无功调节电压控制策略

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