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A novel dual-beam terahertz leaky-wave antenna based on spoof surface plasmon waveguide

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Optoelectronics Letters 2022年第7期18卷 404-407页

作者： bai yukun LIU Song Tianjin Key Laboratory of Film Electronic and Communication Devices Engineering Research Center of Optoelectronic Devices and Communication TechnologyMinistry of EducationSchool of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China

A novel dual-beam terahertz(THz)leaky-wave antenna(LWA)based on triple-periodically(TP)modulated spoof surface plasmon(SSP)waveguide is proposed.It is shown that SSP can be effectively excited and propagated along the surface of parallel corrugated metallic strips.Through proper design,the n=-1 and n=-2 Floquet modes are brought into the leakage radiation region simultaneously.Consequently,the forward and backward propagating waves corresponding to the two modes respectively generate two radiation beams in the far-field region.The proposed antenna is capable of steering the forward beam within a range of 34°and the backward beam within a range of 48°when frequency is swept between 0.23 THz and 0.29 THz.A simulated peak gain of 11.4 dBi and gain variation of 2.87 dBi are achieved within the band.The proposed LWA can be applied in THz wireless communication and radar systems.

关键词： antenna waveguide beam

A wide-band continuous-beam-scanning leaky-wave antenna with a stable gain fed by spoof surface plasmon polaritons

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Optoelectronics Letters 2022年第4期18卷 210-214页

作者： CHAI Bo LI Yajing bai yukun Engineering Research Center of Communication Devices and Technology Ministry of EducationSchool of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China Shanghai University Shanghai 200072China

A leaky-wave antenna(LWA)supporting wide-band and continuous-beam scanning is proposed in this paper.It is based on a spoof surface plasmon polariton(SSPP)transmission line(TL)periodically loaded with circular patches.The optimized antenna structure enables its continuous-beam scanning of 69°from backward through broadside to forward with a stable high radiation gain as the operating frequency increases from 7 GHZ to 15 GHz(with a relative bandwidth of 72.73%).Furthermore,a perfect electronic conductor(PEC)reflector is added at a distance of about 0.3λ_(0)(λ_(0) is the vacuum wavelength for the broadside radiation)to improve the antenna gain,achieving a gain increase of about 3 d B.The proposed LWA is expected to find applications in planar wireless communication systems.

关键词： antenna beam continuous

Groundwater contaminant source identification considering unknown boundary condition based on an automated machine learning surrogate

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Geoscience Frontiers 2024年第1期15卷 402-416页

作者： Yaning Xu Wenxi Lu Zidong Pan Chengming Luo yukun bai Shuwei Qiu Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin UniversityChangchun 130021China Jilin Provincial Key Laboratory of Water Resources and Environment Jilin UniversityChangchun 130021China College of New Energy and Environment Jilin UniversityChangchun 130021China School of Water Resources and Environment Hebei GEO UniversityShijiazhuang 050031China

Groundwater contamination source identification(GCSI)is a prerequisite for contamination risk evaluation and efficient groundwater contamination remediation programs.The boundary condition generally is set as known variables in previous GCSI studies.However,in many practical cases,the boundary condition is complicated and cannot be estimated accurately in advance.Setting the boundary condition as known variables may seriously deviate from the actual situation and lead to distorted identification results.And the results of GCSI are affected by multiple factors,including contaminant source information,model parameters,boundary condition,etc.Therefore,if the boundary condition is not estimated accurately,other factors will also be estimated inaccurately.This study focuses on the unknown boundary condition and proposed to identify three types of unknown variables(contaminant source information,model parameters and boundary condition)innovatively.When simulation-optimization(S-O)method is applied to GCSI,the huge computational load is usually reduced by building surrogate models.However,when building surrogate models,the researchers need to select the models and optimize the hyperparameters to make the model powerful,which can be a lengthy process.The automated machine learning(AutoML)method was used to build surrogate model,which automates the model selection and hyperparameter optimization in machine learning engineering,largely reducing human operations and saving time.The accuracy of AutoML surrogate model is compared with the surrogate model used in eXtreme Gradient Boosting method(XGBoost),random forest method(RF),extra trees regressor method(ETR)and elasticnet method(EN)respectively,which are automatically selected in AutoML engineering.The results show that the surrogate model constructed by AutoML method has the best accuracy compared with the other four methods.This study provides reliable and strong support for GCSI.

关键词： Groundwater contamination source Boundary condition Automated machine learning Surrogate model

Terahertz dual-beam leaky-wave antenna based on composite spoof surface plasmon waveguide

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Optoelectronics Letters 2023年第2期19卷 72-76页

作者： bai yukun LI Sen Tianjin Key Laboratory of Film Electronic and Communication Devices Engineering Research Center of Optoelectronic Devices and Communication TechnologyMinistry of EducationSchool of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 300384China

In this paper, we propose a single-port dual-beam leaky-wave antenna(LWA) in the terahertz(THz) band based on a composite spoof surface plasmon polariton(SSPP) waveguide. The antenna can generate three independent transmission channels by exciting two independent modes inherent to hole and groove structures, respectively. By periodic modulation of the hole and groove structures, we achieve dual-beam scanning through a broad radiation angle using only the -1st space harmonics of the two modes, hence avoiding the instability of the -2rd space harmonic. Within the operating frequency range of 0.62—0.85 THz, the gain ranges from 13.5 d Bi to 17 d Bi for the backward beam, and from 6 d Bi to 11.8 d Bi for the forward beam. The antenna can accomplish continuous backward beam through broadside to forward beam scanning with a total scanning range of 116° and an average efficiency of about 92%. The antenna exhibits a great potential in the design of multi-transceiver radar system in the THz band and multi-beam LWAs.

关键词： Terahertz dual-beam leaky-wave antenna plasmon waveguide

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基于人工表面等离子激元的宽带谐振天线

传感器与微系统 2024年第5期43卷 98-100,104页

作者：杨雅静白育堃天津理工大学集成电路科学与工程学院天津300384

针对传统微带和介质谐振天线(DRA)带宽较窄和尺寸较大的问题,提出了一种基于人工表面等离子激元波导谐振腔的宽带天线。该天线人工表面等离子激元(SSPPs)波导由对称的H型单元结构组成,谐振腔由同轴探针馈电,利用波导单元偶模和奇模两种... 详细信息

针对传统微带和介质谐振天线(DRA)带宽较窄和尺寸较大的问题,提出了一种基于人工表面等离子激元波导谐振腔的宽带天线。该天线人工表面等离子激元(SSPPs)波导由对称的H型单元结构组成,谐振腔由同轴探针馈电,利用波导单元偶模和奇模两种模式的色散特性,实现了天线带宽的显著增大。该天线工作频段为8.8~12.4 GHz,相对带宽为33.9%。在工作频带内,天线的辐射效率大于92%,最大增益达到了6.8 dBi。此外,天线为低剖面结构,整体尺寸较小,结构简单,利于各种无线通信和传感系统的集成。

关键词：宽带天线人工表面等离子激元奇偶模式探针馈电

自供电光电化学传感在食品安全快速检测中的研究进展

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分析试验室 2024年第2期43卷 161-167页

作者：张晓艺王小敏白宝清尉立刚张锦华郭彩霞杨钰昆山西大学生命科学学院太原030006 山西中医药大学中药与食品工程学院晋中030619

食品安全是重大民生问题,食品安全检测则是食品安全管理的重要环节。发展小型化、低能耗、高灵敏的食品安全快速检测技术不仅符合我国国情,而且在食品安全监管人员进行即时检测方面极具现实意义。自供电光电化学传感是基于光电活性材料... 详细信息

食品安全是重大民生问题,食品安全检测则是食品安全管理的重要环节。发展小型化、低能耗、高灵敏的食品安全快速检测技术不仅符合我国国情,而且在食品安全监管人员进行即时检测方面极具现实意义。自供电光电化学传感是基于光电活性材料发生光诱导电子-空穴转移的分析方法,它将从环境中获取的太阳能转化为维持传感器运行的电能,替代了对传统电池的使用,有利于设备无线化、便携化和低耗能。同时,它无需施加电压即可实现对目标物的检测,避免了溶液中还原产物的氧化造成的信号不稳定,从而提高传感检测的灵敏度和在生物分子检测中的应用。本文总结了自供电光电化学传感器的机制、分类及其在食品安全快速检测中的研究进展,探讨了该类无线、可持续、低能耗传感器在现场检测中的应用前景,为食品安全快速检测提供有效的技术支持。

关键词：食品安全自供电光电化学传感器食品安全危害因子

Determination of trophic levels of marine fish in the Yellow Sea and northern East China Sea using nitrogen stable isotope (δ^(15)N) analysis of otoliths

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Journal of Oceanology and Limnology 2022年第2期40卷 634-642页

作者： Huaiyu bai yukun WANG Tingting ZHANG Fangqun DAI Lingfeng HUANG Yao SUN College of the Environment and Ecology Xiamen UniversityXiamen 361102China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery SciencesQingdao 266071China Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems Xiamen UniversityXiamen 361005China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266071China

Fish otolithδ^(15) N(δ^(15) N_(oto))is a demonstrated source of information of dietary history for marine fi sh as it is available iN_(oto)lith archives and sedimentary deposits unlike white muscle tissue(WMT).WMT and stomach content data are insufficient for trophic level(TL)data of past fi shes which is important for the changes of marine fi shery resources over long time scales.To determine the correlation betweenδ^(15) N_(oto) and fi sh WMTδ^(15) N(δ^(15) N_(wmt))and the feasibility of usingδ^(15) N_(oto) in characterizing the TLs of marine fi shes,we conducted nitrogen stable isotope analysis(SIA)in the otolith and WMT of 36 marine fi sh species sampled from the Yellow Sea and northern East China Sea in 2011-2014.Bothδ^(15) N_(oto) andδ^(15) N_(wmt) were analyzed using an elemental analyzer coupled with an isotope ratio mass spectrometer(EA-IRMS).Multiple otoliths were combined to make each otolith measurement and were analyzed as-is without a carbonate dissolution pre-processing step.δ^(15) N_(oto) andδ^(15) N_(wmt) comparisons for species in the Yellow Sea and northern East China Sea are currently lacking and would be helpful for both regional studies and for increasing the number of species for whichδ^(15) N_(oto) andδ^(15) N_(wmt) have been compared.Additionally,to determine the relative accuracy of trophic level calculated usingδ^(15) N_(oto),we compared TL calculated fromδ^(15) N_(oto) to traditional trophic level metrics calculated usingδ^(15) N_(wmt).The results showed a positive and highly signifi cant correlation(R=0.780,P<0.001)betweenδ^(15) N_(oto) andδ^(15) N_(wmt).Trophic level estimation using WMT(TL wmt)and otolith(TL oto)showed congruence in our study,which is not entirely surprising given thatδ^(15) N_(oto) was regressed againstδ^(15) N_(wmt) and the resulting regression coefficient was used to convertδ^(15) N_(oto) toδ^(15) N_(wmt) prior to calculating TL oto.This conversion was required in order to be consistent with previousδ^(15) N_(wmt)-based calculations of TL for comparison.TL oto ca

关键词： stable isotope analysis δ^(15)N otolith trophic level

不同组分体外成熟培养基对绵羊卵母细胞成熟、代谢及孤雌胚胎发育的影响

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黑龙江畜牧兽医 2024年第8期 46-53,59页

作者：张楠宋宇琨岱红艳白雪王俊兰韩僖彤张家新内蒙古农业大学动物科学学院呼和浩特010018 内蒙古自治区羊遗传育种与繁殖重点实验室呼和浩特010018

为了探究不同组分体外成熟培养基对绵羊卵母细胞体外成熟的影响,试验从健康绵羊卵巢中分离卵丘-卵母细胞复合体(COCs),将分离的COCs分为V-FSH+LH+E_(2)+FBS组、V-FSH+FBS组、V-FSH+LH+E_(2)+BSA组、P-FSH+LH+E_(2)+FBS组、P-FSH+FBS组、P-FSH+LH+E_(2)+BSA组,每组分别添加以V-促卵泡素(FSH,垂体中提纯的FSH)和P-FSH(体外基因重组表达的FSH)为基础设计的体外成熟培养基以进行体外成熟试验,即各组依次添加V-FSH+促黄体素(LH)+雌激素(E_(2))+胎牛血清(FBS)、V-FSH+FBS、V-FSH+LH+E_(2)+牛血清白蛋白(BSA)、P-FSH+LH+E_(2)+FBS、P-FSH+FBS、P-FSH+LH+E_(2)+BSA体外成熟培养基,体外成熟后检测各组卵丘扩展指数(CEI)、第一极体排出率、卵母细胞氧化还原态、乳酸生成量、葡萄糖消耗量、ATP生成量;统计孤雌胚胎的卵裂率、囊胚率、囊胚细胞数,比较不同组分体外成熟培养基对卵母细胞成熟、代谢及孤雌胚胎发育的影响。结果表明:V-FSH+LH+E_(2)+FBS组CEI最高,除与P-FSH+FBS组差异不显著外(P>0.05),与其他组均差异显著(P0.05)。V-FSH+LH+E_(2)+FBS组、P-FSH+FBS组、P-FSH+LH+E_(2)+BSA组的相对氧化还原比均接近1且差异不显著(P>0.05),但均显著低于其他组(P0.05)外,显著高于其他组(P0.05),但均显著高于其他组(P0.05),但均显著低于其他组(P0.05),但各组的囊胚细胞数差异不显著(P>0.05)。说明不同来源的FSH与不同组分协同作用会对绵羊卵母细胞的成熟、代谢及孤雌胚胎发育产生不同的效果,并影响了其后续胚胎的发育能力。

关键词：绵羊卵母细胞促卵泡素(FSH) 体外成熟细胞代谢

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热解碳泡沫材料吸波机理研究

材料导报 2024年第1期38卷 17-23页

作者：林立海李处森颜雨坤白炜琛刘利冉张劲松中国科学院金属研究所沈阳110016 中国科学技术大学材料科学与工程学院合肥230026

为避开高分子材料作为基体,进一步拓展碳系吸波材料在空间环境或仿空间环境中的应用,本工作提出了预制体法结合热解工艺制备热解碳泡沫吸波材料的新思路,采取从400℃到1 500℃的不同目标热解温度制备了一系列热解碳泡沫材料,通过对不同... 详细信息

为避开高分子材料作为基体,进一步拓展碳系吸波材料在空间环境或仿空间环境中的应用,本工作提出了预制体法结合热解工艺制备热解碳泡沫吸波材料的新思路,采取从400℃到1 500℃的不同目标热解温度制备了一系列热解碳泡沫材料,通过对不同温度热解碳泡沫材料的傅里叶红外光谱、热重-差热、X射线衍射和电化学分析,明确了热解碳泡沫为半导体材料,其热解残余基团无序区造成的阈值效应、共轭效应和位阻效应抑制π电子离域移动,控制载流子浓度,进而影响热解碳泡沫材料的电磁性能。对不同温度热解碳泡沫材料电磁参数的测试表明,600~700℃热解的碳泡沫材料的介电常数实部和虚部大小适合,适合作吸波材料。

关键词：碳泡沫吸波材料热解半导体空间环境热真空