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Single-shot phase retrieval for randomly fluctuated and obstructed vortex beams

Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 72-80页

作者： Hao zhang Jun’an Zhu xingyuan Lu Zhiquan Hu Jianbo Gao Kun Liu Qiwen Zhan Yangjian Cai Chengliang Zhao School of Physical Science and Technology Soochow UniversitySuzhou 215006China School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China Shandong Provincial Engineering and Technical Center of Light Manipulations Shandong Provincial Key Laboratory of Optics and Photonic DeviceSchool of Physics and ElectronicsShandong Normal UniversityJinan 250358China Joint Research Center of Light Manipulation Science and Photonic Integrated Chip of East China Normal University and Shandong Normal University East China Normal UniversityShanghai 200241China

Vortex beams with orbital angular momentum play a crucial role in increasing the information capacity in optical communications.The magnitude of orbital angular momentum determines the ability of information encoding.In practice,a vortex beam can encounter random objects or turbulence during free-space propagation,resulting in information damage.Therefore,accurately measuring the orbital angular momentum of a randomly fluctuated and obstructed vortex beam is a considerable challenge.Herein,we propose a single-shot method for the phase retrieval of a randomly fluctuated and obstructed vortex beam by combining the phase-shift theorem and self-reference holography.Experimental results reveal that the sign and magnitude of the initial orbital angular momentum can be simultaneously determined based on their quantitative relation with the number of coherence singularities on the observation plane,thus addressing the effects of random occlusion and atmospheric turbulence.The proposed method considerably improved the accurate decoding of orbital angular momentum information in nonideal freespace optical communications.

关键词： optical vortex phase retrieve orbital angular momentum measurement antiturbulence antidisturbance

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Terahertz bound states in the continuum with incident angle robustness induced by a dual period metagrating

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Photonics Research 2022年第3期10卷 810-819页

作者： Wenqiao Shi Jianqiang Gu xingyuan zhang Quan Xu Jiaguang Han Quanlong Yang Longqing Cong Weili zhang Center for Terahertz Waves and College of Precision Instrument and Optoelectronics Engineering Tianjin Universityand Key Laboratory of Optoelectronics Information and TechnologyMinistry of EducationTianjin 300072China Nonlinear Physics Centre Australian National UniversityCanberraACT 2601Australia Department of Electrical and Electronic Engineering Southern University of Science and TechnologyShenzhen 518055China School of Electrical and Computer Engineering Oklahoma State UniversityStillwaterOklahoma 74078USA

Metasurface-empowered bound state in the continuum(BIC)provides a unique route for fascinating functional devices with infinitely high quality factors.This method is particularly attractive to the terahertz community because it may essentially solve the deficiencies in terahertz filters,sensors,lasers,and nonlinear sources.However,most BIC metasurfaces are limited to specified incident angles that seriously dim their application prospects.Here,we propose that a dual-period dielectric metagrating can support multiple families of BICs that originate from guided mode resonances in the dielectric grating and exhibit infinite quality factors at arbitrarily tilted incidence.This robustness was analyzed based on the Bloch theory and verified at tilted incident angles.We also demonstrate that inducing geometric asymmetry is an efficient way to manipulate the leakage and coupling of these BICs,which can mimic the electromagnetically induced transparency(EIT)effect in our dual-period metagrating.In this demonstration,a slow-light effect with a measured group delay of 117 ps was achieved.The incidence-insensitive BICs proposed here may greatly extend the application scenarios of the BIC effect.The high Q factor and outstanding slow-light effect in the metagrating show exciting prospects in realizing high-performance filters,sensors,and modulators for prompting terahertz applications.

关键词： incident dielectric continuum

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Revisit of the anisotropic vortex states of 2H-NbSe_(2) towards the zero-field limit

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Chinese Physics B 2024年第6期33卷 80-86页

作者：张凡侯兴元姜宇轩张宗源涂玉兵朱相德陈根富单磊 Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Center of Free Electron Laser and High Magnetic Field Anhui UniversityHefei 230601China Information Materials and Intelligent Sensing Laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials in Anhui University Ministry of EducationHefei 230601China School of Physics and Materials Science Anhui UniversityHefei 230601China Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions High Magnetic Field LaboratoryHFIPSAnhuiChinese Academy of Sciencesand University of Science and Technology of ChinaHefei 230031China Hefei National Laboratory Hefei 230088China

We revisited the vortex states of 2H-NbSe_(2) towards zero fields by a low-temperature scanning tunneling microscope.Fine structures of the anisotropic vortex states were distinguished, one is a spatially non-splitting zero bias peak, and the other is an in-gap conductance anomaly resembling evolved crossing features around the center of the three nearest vortices.Both of them distribute solely along the next nearest neighboring direction of the vortex lattice and become unresolved in much higher magnetic fields, implying an important role played by the vortex–vortex interactions. To clarify these issues,we have studied the intrinsic vortex states of the isolated trapped vortex in zero fields at 0.45 K. It is concluded that the anisotropic zero bias peak is attributed to the superconducting gap anisotropy, and the spatially evolved crossing features are related to the vortex–vortex interaction. The vortex core size under the zero-field limit is determined. These results provide a paradigm for studying the inherent vortex states of type-II superconductors especially based on an isolated vortex.

关键词： vortex states zero-bias conductance peak scanning tunneling microscopy

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结合道路信息的HEV发动机起停触发系统设计

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重庆交通大学学报（自然科学版） 2024年第7期43卷 121-128,136页

作者：高爱云张兴源付主木河南科技大学车辆与交通工程学院河南洛阳471003 河南科技大学信息工程学院河南洛阳471023

现有的发动机起停系统只要发动机满足怠速停止的基本条件发动机就会停止,造成车辆频繁起停,这样不仅会加剧发动机部件磨损,还会增加整车油耗。为解决这一问题,设计了一种结合道路信息的混合动力汽车发动机起停触发系统(HEV-EST)。根据HE... 详细信息

现有的发动机起停系统只要发动机满足怠速停止的基本条件发动机就会停止,造成车辆频繁起停,这样不仅会加剧发动机部件磨损,还会增加整车油耗。为解决这一问题,设计了一种结合道路信息的混合动力汽车发动机起停触发系统(HEV-EST)。根据HEV发动机怠速和重起油耗图,确定HEV-EST起停条件;利用BP神经网络数字识别算法和颜色识别算法构建交通信号灯识别模型;运用统筹学的排队论对交通流进行分析计算,构建交通流分析模型;最后结合交通信号灯识别模型和交通流分析模型,设计了HEV-EST;并进行了MATLAB仿真验证。结果表明:该系统明显降低了车辆无效起停的次数,提高了整车燃油经济性。

关键词：车辆工程混合动力汽车交通信号灯识别交通流发动机起停

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Macroporous-mesoporous C-,S-,N-doped titania microspheres via the polyHIPE microspheres templates

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Chinese Chemical Letters 2021年第3期32卷 1135-1138页

作者： Xiaoling Cui Huarong Liu xingyuan zhang Hewen Liu CAS Key Laboratory of Soft Matter Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China

Doping and increasing specific surface area by forming highly porous structures are two effective ways to enhance the photocatalytic performances of TiO_(2) particles.He re for the first time,we report a new facile method to prepare the macroporous-mesoporous C-,S-,N-doped TiO_(2)(C/S/N-TiO_(2))microspheres via polyHIPE microsphe res as templates.The chemical and crystalline structure s of these hierarchical porous TiO_(2) microspheres are analyzed with FTIR,XPS,EDS,and XRD.The macroporous-mesoporous structures are confirmed with SEM observation and BET analysis.UV-vis DRS spectra analysis shows that the band gaps of C doped TiO_(2),C/N doped TiO_(2),C/S doped TiO_(2) and C/S/N doped TiO_(2) are estimated to be 3.07,3.01,2.94 and 2.81 eV,respectively,which are significantly narrower than that of TiO_(2) nanoparticles(3.23 eV).Photoluminescence spectra demonstrate that the recombination of electrons and holes in these macroporous-mesoporous TiO_(2) microspheres is also suppressed.The hierarchical porous C/S/N-TiO_(2) microspheres show high visible-light catalytic efficiency and excellent cycling stability to degrade RhB dye.

关键词： Porous titania microspheres PolyHIPE microspheres Hierarchical porous structure Heteroatom doping Photocatalysis

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Association Between Lipid Profiles and Left Ventricular Hypertrophy:New Evidence from a Retrospective Study

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Chinese Medical Sciences Journal 2022年第2期37卷 103-117页

作者： Xuewei Huang Keqiong Deng Juanjuan Qin Fang Lei xingyuan zhang Wenxin Wang Lijin Lin Yuming Zheng Dongai Yao Huiming Lu Feng Liu Lidong Chen Guilan zhang Yueping Liu Qiongyu Yang Jingjing Cai Zhigang She Hongliang Li Department of Cardiology Renmin Hospital of Wuhan UniversityWuhan 430060China Department of Cardiology Center Hospital of HuanggangHuanggangHubei 438000China Huanggang Institute of Translaten Medicine HuanggangHubei 438000China Department of Cardiology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Institute of Model Animal Wuhan UniversityWuhan 430071China School of Basic Medical Science Wuhan UniversityWuhan 430071China Physical Examination Center The Central Hospital of WuhanWuhan 430014China Physical Exami nation Center Zhongnan Hospital of Wuhan UniversityWuhan 430071China General Medical Department CR&WISCO General HospitalWuhan 430000China In formation Center Hubei Provincial Hospital of Integrated Chinese and Western MedicineWuhan 430015China Department of Medical Examination Center Taihe HospitalHubei University of MedicineShiyanHubei 442000China Department of Health Management Xiaogan Hospital Affiliated to Wuhan University of Science and TechnologyXiaoganHubei 432000China Basic Medical Laboratory General Hospital of Central Theater CommandWuhan 430070China Hubei Key Laboratory of Central Nervous System Tumor and Intervention Wuhan 430070China Chinese Medicine Center Shiyan Renmin HospitalShiyanHubei 442000China Department of Cardiology The Third Xiangya HospitalCentral South UniversityChangsha 410000China

Objective To explore the association between lipid profiles and left ventricular hypertrophy in a Chinese general population.Methods We conducted a retrospective observational study to investigate the relationship between lipid markers[including triglycerides,total cholesterol,low-density lipoprotein cholesterol,high-density lipoprotein(HDL)cholesterol,non-HDL-cholesterol,apolipoprotein A-I,apolipoprotein B,lipoprotein[a],and composite lipid profiles]and left ventricular hypertrophy.A total of 309,400 participants of two populations(one from Beijing and another from nationwide)who underwent physical examinations at different health management centers between 2009 and 2018 in China were included in the cross-sectional study.7,475 participants who had multiple physical examinations and initially did not have left ventricular hypertrophy constituted a longitudinal cohort to analyze the association between lipid markers and the new-onset of left ventricular hypertrophy.Left ventricular hypertrophy was measured by echocardiography and defined as an end-diastolic thickness of the mterventricular septum or left ventricle posterior wall>11 mm.The Logistic regression model was used in the cross-sectional study.Cox model and Cox model with restricted cubic splines were used in the longitudinal cohort.Results In the cross-sectional study for participants in the highest tertile of each lipid marker compared to the respective lowest,triglycerides[odds ratio(OR):1.2S0,95%CI:1.060 to 1.474],HDL-cholesterol(OR:0.780,95%CI:0.662 to 0.918),and lipoprotein(a)(OR:1.311,95%C7:1.115 to 1.541)had an association with left ventricular hypertrophy.In the longitudinal cohort,for participants in the highest tertile of each lipid marker at the baseline compared to the respective lowest,triglycerides[hazard ratio(HR):3.277,95%C/:1.720 to 6.244],HDL-cholesterol(HR:0.516,95%C7:0.283 to 0.940),non-HDL-cholesterol(HR:2.309,95%C/:1.296 to 4.112),apolipoprotein B(HR:2.244,95%CI:1.251 to 4.032)showed an association with new-onset left ventricular hy

关键词： left ventricular hypertrophy lipid triglycerides apolipoprotein

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社会与情感能力如何影响学生的公共参与?——基于第二轮SSES测评数据

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华东师范大学学报（教育科学版） 2024年第5期42卷 99-111页

作者：唐汉卫张红高星原华东师范大学基础教育改革与发展研究所华东师范大学教育学系上海200062

积极有效的公共参与是培养学生成为“时代新人”的关键。研究利用Survey on Social and Emotional Skills(SSES 2023)的中国济南调查数据,考察10岁和15岁组学生的公共参与现状,并探究社会与情感能力对公共参与的影响及其作用机制。结果... 详细信息

积极有效的公共参与是培养学生成为“时代新人”的关键。研究利用Survey on Social and Emotional Skills(SSES 2023)的中国济南调查数据,考察10岁和15岁组学生的公共参与现状,并探究社会与情感能力对公共参与的影响及其作用机制。结果发现:(1)超半数参与调查的学生未参加过环境保护和志愿服务相关的公共活动,公共参与人数随参与频率的增加而降低,且10岁组学生公共参与频率显著高于15岁组学生;(2)果敢、创造性与成就动机是影响学生公共参与的关键能力,其对公共参与的重要性优于其他社会与情感能力;(3)社会与情感能力不仅直接影响学生的公共参与,还通过同学关系的中介路径、学校归属感的中介路径以及同学关系和学校归属感的链式中介路径间接影响学生的公共参与。研究揭示了社会与情感能力在公民教育中的重要作用,启示以社会与情感能力为抓手,多举措提升学生的公共参与水平。

关键词：社会与情感能力公共参与学校归属感同学关系

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Superconducting state in Ba_((1-x)) Sr_(x)Ni_(2)As_(2) near the quantum critical point

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Chinese Physics B 2024年第6期33卷 488-493页

作者：余承峰张宗源宋林兴吴彦玮袁小秋侯杰涂玉兵侯兴元李世亮单磊 Information Materials and Intelligent Sensing Laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China Key Laboratory of Structure and Functional Regulation of Hybrid Materials(Anhui University) Ministry of EducationHefei 230601China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China Songshan Lake Materials Laboratory Dongguan 523808China

In the phase diagram of the nickel-based superconductor Ba_(1-x)Sr_(x)Ni_(2)As_(2),T_(C) has been found to be enhanced sixfold near the quantum critical point(QCP) x=0.71 compared with the parent compound.However,the mechanism is still under debate.Here,we report a detailed investigation of the superconducting properties near the QCP(x≈0.7) by utilizing scanning tunneling microscopy and spectroscopy.The temperature-dependent superconducting gap and magnetic vortex state were obtained and analyzed in the framework of the Bardeen-Cooper-Schrieffer model.The ideal isotropic s-wave superconducting gap excludes the long-speculated nematic fluctuations while preferring strong electron-phonon coupling as the mechanism for T_(C) enhancement near the QCP.The lower than expected gap ratio of Δ/(k_(B) T_(C)) is rooted in the fact that Ba_(1-x)Sr_(x)Ni_(2)As_(2) falls into the dirty limit with a serious pair breaking effect similar to the parent compound.

关键词： nickel-based superconductor electron–phonon coupling dirty limit scanning tunneling microscopy/spectroscopy

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Rail fastener defect inspection method for multi railways based on machine vision

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Railway Sciences 2022年第2期1卷 210-223页

作者： Junbo Liu YaPing Huang ShengChun Wang XinXin Zhao Qi Zou xingyuan zhang Infrastructure Inspection Research Institute China Academy of Railway Sciences Corporation LimitedBeijingChina Beijing Key Laboratory of Traffic Data Analysis and Mining Beijing Jiaotong UniversityBeijingChina Beijing R&D Centre Huawei Technologies Co LtdShenzhenChina

Purpose–This research aims to improve the performance of rail fastener defect inspection method for multi railways,to effectively ensure the safety of railway operation.Design/methodology/approach–Firstly,a fastener region location method based on online learning strategy was proposed,which can locate fastener regions according to the prior knowledge of track image and template matching method.Online learning strategy is used to update the template library dynamically,so that the method not only can locate fastener regions in the track images of multi railways,but also can automatically collect and annotate fastener samples.Secondly,a fastener defect recognition method based on deep convolutional neural network was proposed.The structure of recognition network was designed according to the smaller size and the relatively single content of the fastener region.The data augmentation method based on the sample random sorting strategy is adopted to reduce the impact of the imbalance of sample size on recognition performance.Findings–Test verification of the proposed method is conducted based on the rail fastener datasets of multi railways.Specifically,fastener location module has achieved an average detection rate of 99.36%,and fastener defect recognition module has achieved an average precision of 96.82%.Originality/value–The proposed method can accurately locate fastener regions and identify fastener defect in the track images of different railways,which has high reliability and strong adaptability to multi railways.

关键词： Rail fastener Defects inspection Multi railways Image recognition Deep convolutional neural network Machine vision

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柔性刷辊式葡萄藤清土机设计与试验

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农业机械学报 2024年第2期55卷 138-148,219页

作者：李金明张佳喜王茂博杨兴元王毅超新疆农业大学机电工程学院乌鲁木齐830052 新疆智能农业装备重点实验室乌鲁木齐830052 乌鲁木齐优尼克生物科技有限公司乌鲁木齐830052 新疆农业大学食品科学与药学学院乌鲁木齐830052

为解决新疆地区现有葡萄藤清土机械伤藤率高、彩条布上方大量覆土影响葡萄藤清土上架和彩条布回收的问题,采用柔性刷辊设计了一种刷辊式葡萄藤清土机。该机关键部件为清土装置,作业时通过清土刷的旋转运动和横向伸缩机构的往复运动将彩... 详细信息

为解决新疆地区现有葡萄藤清土机械伤藤率高、彩条布上方大量覆土影响葡萄藤清土上架和彩条布回收的问题,采用柔性刷辊设计了一种刷辊式葡萄藤清土机。该机关键部件为清土装置,作业时通过清土刷的旋转运动和横向伸缩机构的往复运动将彩条布上方的覆土清除。首先进行清土刷结构设计和材料选择,然后对清土刷工作过程进行运动学理论分析,得到影响清土机作业性能的主要参数。通过单因素试验确定清土刷转速、横向伸缩机构往复速度、清土刷回转直径的合理取值范围,以清土刷转速、横向伸缩机构往复速度、清土刷回转直径为试验因素,以清土率和伤藤率为评价指标,开展三因素三水平正交试验。试验结果表明,各试验影响因素对清土率和伤藤率的影响显著性大小顺序为清土刷转速、横向伸缩机构往复速度、清土刷回转直径。较优参数组合为:清土刷转速250 r/min、横向伸缩机构往复速度0.14 m/s和清土刷回转直径600 mm,在此参数组合下进行3次验证试验取平均值,清土率为90.98%,伤藤率为3.27%,与优化值相对误差均小于5%,证明样机设计合理。

关键词：刷辊式葡萄藤清土机正交试验

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