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Clean Energy 2023年第1期7卷 139-147页

作者： Yufeng Qin Chaoyong Sun shaojie ke Rou Wen Yifan Wang Jing Ji Meiling Dou State key Laboratory of Chemical Resource Engineering Laboratory of Electrochemical Process and Technology for materialsBeijing University of Chemical TechnologyBeijing 100029China

High-purity of hydrogen is vital to the guarantee of end usage in proton exchange membrane fuel cell(PEMFC)electric vehicles(EVs)with superior durability and low ***,the currently employed hydrogen,primarily from fossil fuel,still contains some poisoning impurities that significantly affect the durability of ***,we investigate the poisoning effect of several typical hydrogen impurities(S^(2-),Cl^(-),HCOO^(-)and CO_(3)^(2-))on the hydrogen oxidation reaction(HOR)of the state-of-the-art carbon-supported platinum(Pt/C)catalyst used in the PEMFC *** results indicate that the electrochemically active surface area of Pt/C is hampered by these hydrogen impurities with reduced effective Pt reactive sites due to the competitive adsorption against hydrogen at Pt sites showing the extent of the poisoning on Pt sites in the order:S^(2-)>Cl^(-)>HCOO^(-)>CO_(3)^(2-).Density functional theory calculations reveal that the adsorption energy of S2-on Pt(111)is greater than that of Cl^(-),HCOO^(-)and CO_(2),and the electronic structure of Pt is found to be changed due to the adsorption of impurities showing the downshift of the d-band centre of Pt that weakens the adsorption of hydrogen on the Pt *** work provides valuable guidance for future optimization of hydrogen quality and also emphasizes the importance of anti-poisoning anode catalyst development,especially towards H_(2)S impurities that seriously affect the durability of PEMFCs.

关键词： hydrogen impurity poisoning effect electronic structure Pt/C hydrogen oxidation catalysis fuel cell

Effect of load-cycling amplitude on performance degradation for proton exchange membrane fuel cell

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Chinese Chemical Letters 2021年第10期32卷 3159-3163页

作者： Kun Wang Ning Li Yanan Yang shaojie ke Zhengping Zhang Meiling Dou Feng Wang State key Laboratory of Chemical Resource Engineering Beijing Key Laboratory of Electrochemical Process and Technology for MaterialsBeijing University of Chemical TechnologyBeijing 100029China Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical TechnologyBeijing 100029China

Durability is one of the critical issues to restrict the commercialization of proton exchange membrane fuel cells(PEMFCs) for the vehicle *** practical dynamic operation significantly affects the PEMFCs durability by corroding its key *** this work,the degradation behavior of a single PEMFC has been investigated under a simulated automotive load-cycling operation,with the aim of revealing the effect of load amplitude(0.8 and 0.2 A/cm2 amplitude for the current density range of0.1-0.9 and 0.1-0.3 A/cm^(2),respectively) on its performance degradation.A more severe degradation on the fuel cell performance is observed under a higher load amplitude of 0.8 A/cm^(2) cycling operation,with$10.5% decrease of cell voltage at a current density of 1.0 A/*** larger loss of fuel cell performance under the higher load amplitude test is mainly due to the frequent fluctuation of a wider potential *** characterizations analyses indicate that the Pt nanoparticles in cathodic catalyst layer grow faster with a higher increase extent of particle size under this circumstance because of their repeated oxidation/reduction and subsequent dissolution/agglomeration process,resulting in the degradation of platinum catalyst and thus the cell ***,the detected microstructure change of the cathodic catalyst layer also contributes to the performance failure that causes a distinct increase in mass transfer resistance.

关键词： Proton exchange membrane fuel cell Durability Load-cycling amplitude Degradation mechanism Platinum catalyst

Tunable topological polaritons by dispersion tailoring of an active metasurface

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Advanced Photonics 2024年第4期6卷 59-69页

作者： shaojie Wang ke Chen Shufang Dong Tian Jiang Junming Zhao Yijun Feng Nanjing University School of Electronic Science and EngineeringNanjingChina

Hyperbolic polaritons are known to exist in materials with extreme anisotropy,exhibiting exotic optical properties that enable a plethora of unusual phenomena in the fields of polaritonics and ***,achieving simultaneous low-dimensionality,high-speed controllability,and on-demand reconfigurability of the polaritons remains unexplored despite their excellent potential in light-matter interactions,photonic integrated circuits,and optoelectronic ***,we propose a metasurface approach to integrating artificially engineered electromagnetic anisotropy with fast-controllable electronic elements,offering a new route to realize active topological *** showcase the proposed reconfigurable metasurface can support real-time transitions of designer polaritons from elliptical to flat,and then to hyperbolic and circular isofrequency ***,the in-plane surface wavefront undergoes the transitions from convex to collimating,concave,and eventually back to *** exploiting the topological variations in polariton dispersions,we observe intriguing phenomena of controllable field canalization and tunable planar ***,we report the concept of a planar reconfigurable integrated polariton circuit by spatially tailoring the distributions of polariton isofrequency contours,unveiling rich dispersion engineering possibilities and active control *** may provide an inspiring platform for developing planar active plasmonic devices with potential applications in subdiffraction-resolution imaging,sensing,and information processing.

关键词： topological transitions hyperbolic metasurface anisotropic polaritons active tuning dispersion engineering

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考虑输入饱和的直升机机动飞行LPV控制

系统工程与电子技术 2022年第2期44卷 637-643页

作者：李硕张绍杰严鹏张涵鲁可南京航空航天大学自动化学院江苏南京211106 中国直升机设计研究所直升机旋翼动力学重点实验室江西景德镇333001

针对直升机机动飞行过程中存在的输入饱和问题,提出了一种基于参数依赖Lyapunov的状态反馈控制方法。首先根据直升机非线性模型建立纵向线性变参数(linear parameter varying,LPV)模型,并采用逆仿真数值分析方法对悬停机动科目进行轨迹... 详细信息

针对直升机机动飞行过程中存在的输入饱和问题,提出了一种基于参数依赖Lyapunov的状态反馈控制方法。首先根据直升机非线性模型建立纵向线性变参数(linear parameter varying,LPV)模型,并采用逆仿真数值分析方法对悬停机动科目进行轨迹建模。基于吸引域与不变集理论,利用参数化线性矩阵不等式(parameterized linear matrix inequalities,PLMI),分析闭环系统的稳定条件。利用松弛变量技术将控制器PLMI条件转化为易于求解的线性矩阵不等式(linear matrix inequalities,LMI)条件,求解悬停机动轨迹跟踪控制律。仿真结果表明了所提模型和控制方法的可行性和有效性。

关键词：线性变参数仿射参数依赖输入饱和机动飞行松弛变量

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工业人工智能及应用研究现状及展望

自动化学报 2020年第10期46卷 2031-2044页

作者：李杰李响许元铭杨绍杰孙可意辛辛那提大学机械工程系俄亥俄45221美国富士康科技集团密尔沃基53177美国

工业4.0将工业制造流程以及产品质量优化从以前依照经验和观察进行判断转变为以事实为基础,通过分析数据进而挖掘潜在价值的完整智能系统.人工智能技术的快速发展在工业4.0的实现中扮演着关键的角色.然而,传统的人工智能技术通常着眼于... 详细信息

工业4.0将工业制造流程以及产品质量优化从以前依照经验和观察进行判断转变为以事实为基础,通过分析数据进而挖掘潜在价值的完整智能系统.人工智能技术的快速发展在工业4.0的实现中扮演着关键的角色.然而,传统的人工智能技术通常着眼于日常生活、社会交流和金融场景,而非解決工业界实际所遇到的问题.相比而言,工业人工智能技术基于工业领域的具体问题,利用智能系统提升生产效率、系统可靠性并优化生产过程,更加适合解决特定的工业问题同时帮助从业人员发现隐性问题,并让工业设备有自主能力来实现弹性生产并最终创造更大价值.本文首先介绍工业人工智能的相关概念,并通过实际的工业应用案例如元件级的滚珠丝杠、设备级的带锯加工机与机器群等不同层次的问题来展示工业人工智能架构的可行性与应用前景.

关键词：工业人工智能智能制造自动化工业4.0

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直升机切换LPV鲁棒跟踪控制

南京航空航天大学学报 2021年第2期53卷 260-266页

作者：张绍杰李硕严鹏鲁可南京航空航天大学自动化学院南京211106 中国直升机设计研究所直升机旋翼动力学重点实验室景德镇333001

针对直升机跟踪控制问题,提出了一种基于模态依赖平均驻留时间(Mode-dependent average dwell time,MDADT)切换信号的线性变参数(Linear variable parameter,LPV)控制方法。在直升机全飞行包线内选取可以表征直升机飞行特性的状态作为... 详细信息

针对直升机跟踪控制问题,提出了一种基于模态依赖平均驻留时间(Mode-dependent average dwell time,MDADT)切换信号的线性变参数(Linear variable parameter,LPV)控制方法。在直升机全飞行包线内选取可以表征直升机飞行特性的状态作为增益调度变量,利用"小扰动"假设将全量方程进行线性化处理并对其配平求解,将复杂的非线性模型转化为可以计算求解的线性模型。采用雅可比线性化方法在非线性模型平衡点处进行线性化处理,使用数据拟合的方法在理论上建立与非线性模型动态接近的LPV模型。对时变参数进行区间划分,结合参数依赖的多Lyapunov函数和MDADT方法,给出了保证切换LPV系统全局一致指数稳定的充分条件。考虑时变参数的渐变特性,以及由于测量误差和参数飘移等因素而造成的控制器增益变化,得到了在MDADT切换信号限制下的切换律。仿真结果表明所设计的控制律能有效动态跟踪直升机前飞的不同状态量,验证了所建模型和控制算法的有效性和可行性。

关键词：直升机线性变参数建模切换多胞系统跟踪控制模态依赖平均驻留时间

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基于载波相位的接收机群时延测量技术

系统工程与电子技术 2022年第4期44卷 1078-1084页

作者：王峰毅肖志斌李蓬蓬张可倪少杰国防科技大学电子科学学院湖南长沙410073

针对传统群时延测量方法无法达到皮秒级测量精度要求的问题,提出一种基于载波相位的接收机群时延测量技术。该方法在通道群时延特性为分段抛物线假设的前提下,利用窄带扩频信号的载波相位观测量对分段抛物线系数进行搜索固定,通过抛物... 详细信息

针对传统群时延测量方法无法达到皮秒级测量精度要求的问题,提出一种基于载波相位的接收机群时延测量技术。该方法在通道群时延特性为分段抛物线假设的前提下,利用窄带扩频信号的载波相位观测量对分段抛物线系数进行搜索固定,通过抛物线函数固定整周模糊度,结合载波相位反映各频点的群时延。仿真结果表明,该测量技术可以精确固定整周模糊度,群时延测量结果可达皮秒量级,对高精度导航接收机群时延特性具有良好的测量效果。

关键词：群时延测量窄带扩频信号整周模糊度载波相位

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正交频分复用系统非线性信道估计算法

西安交通大学学报 2005年第6期39卷 637-640页

作者：缪科张太镒孙建成汤少杰西安交通大学电子与信息工程学院西安710049

为了提高正交频分复用(OFDM)系统的传输质量和有效性,提出了一种基于最小二乘支持向量机的OFDM非线性信道估计算法.通过在OFDM符号中插入导频而获得训练数据,利用最小二乘支持向量机将训练数据映射到高维空间,并在此空间采用结构风险最... 详细信息

为了提高正交频分复用(OFDM)系统的传输质量和有效性,提出了一种基于最小二乘支持向量机的OFDM非线性信道估计算法.通过在OFDM符号中插入导频而获得训练数据,利用最小二乘支持向量机将训练数据映射到高维空间,并在此空间采用结构风险最小化准则对时变信道频率响应函数进行回归估计,把低维空间的非线性估计转化为高维空间的线性估计,提高了估计的精度.仿真结果表明,该算法能够有效地减小由多径引起的频率选择性衰落的影响,与传统算法相比,在同一误码率条件下的信噪比提高了3～7dB.

关键词：正交频分复用信道估计最小二乘支持向量机时变信道

Pan-omics-based characterization and prediction of highly multidrugadapted strains from an outbreak fungal species complex

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The Innovation 2024年第5期5卷 101-109,100页

作者： Xin Fan Lei Chen Min Chen Na Zhang Hong Chang Mingjie He Zhenghao Shen Lanyue Zhang Hao Ding Yuyan Xie Yemei Huang Weixin ke Meng Xiao Xuelei Zang Heping Xu Wenxia Fang shaojie Li Cunwei Cao Yingchun Xu Shiguang Shan Wenjuan Wu Changbin Chen Xinying Xue Linqi Wang Department of Infectious Diseases and Clinical Microbiology Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China Beijing Research Center for Respiratory Infectious Diseases Beijing 100020China State key Laboratory of Mycology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Department of Dermatology Shanghai Key Laboratory of Molecular Medical MycologyChangzheng HospitalShanghai 200003China University of Chinese Academy of Sciences Beijing 100049China key Laboratory of Intelligent Information Processing Institute of Computing TechnologyChinese Academy of SciencesBeijing 100190China Department of Respiratory and Critical Care Emergency and Critical Care Medical CenterBeijing Shijitan HospitalCapital Medical UniversityBeijing 100038China Department of Laboratory Medicine State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Beijing key Laboratory for Mechanisms Research and Precision Diagnosis of Invasive Fungal Diseases Beijing 100730China Department of Clinical Laboratory First Affiliated Hospital of Xiamen UniversityXiamen 361003China Institute of Biological Science and Technology Guangxi Academy of SciencesNanning 530007China Department of Dermatology The First Affiliated Hospital of Guangxi Medical UniversityNanning 530021China Guangxi key Laboratory of Mycosis Prevention and Treatment Nanning 530021China Department of Laboratory Medicine Shanghai East HospitalTongji University School of MedicineShanghai 200120China The Unit of Pathogenic Fungal Infection&Host Immunity Shanghai Institute of Immunity and InfectionChinese Academy of SciencesShanghai 200031China Nanjing Advanced Academy of Life and Health Nanjing 211135China Department of Respiratory and Critical Care Shandong Second Medical UniversityWeifang 261035China

Strains from the Cryptococcus gattii species complex(CGSC)have caused the Pacific Northwest cryptococcosis outbreak,the largest cluster of lifethreatening fungal infections in otherwise healthy human hosts known to *** this study,we utilized a pan-phenome-based method to assess the fitness outcomes of CGSC strains under 31 stress conditions,providing a comprehensive overview of 2,821 phenotype-strain associations within this pathogenic *** clustering analysis revealed a strong correlation between distinct types of stress phenotypes in a subset of CGSC strains,suggesting that shared determinants coordinate their adaptations to various ***,a specific group of strains,including the outbreak isolates,exhibited a remarkable ability to adapt to all three of the most commonly used antifungal drugs for treating cryptococcosis(amphotericin B,5-fluorocytosine,and fluconazole).By integrating pan-genomic and pan-transcriptomic analyses,we identified previously unrecognized genes that play crucial roles in conferring multidrug resistance in an outbreak strain with high multidrug *** these genes,we identified biomarkers that enable the accurate prediction of highly multidrug-adapted CGSC strains,achieving maximum accuracy and area under the curve(AUC)of 0.79 and 0.86,respectively,using machine learning ***,we developed a pan-omic approach to identify cryptococcal multidrug resistance determinants and predict highly multidrug-adapted CGSC strains that may pose significant clinical concern.

关键词： multidrug adapted prediction

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赤泥基层状金属氧化物对2种常见染料的吸附

环境工程学报 2017年第3期11卷 1402-1408页

作者：钱翌周绍杰青岛科技大学环境与安全工程学院青岛266042

以赤泥为原料采用焙烧还原-重构法制备层状金属氢氧化物(LDH)和层状金属氧化物(LDO),比较了赤泥、焙烧赤泥、LDO和LDH对活性黄ke-4R染料(ke-4R)、活性艳蓝染料(RBB)的吸附效果;考察了吸附剂用量、吸附温度、吸附时间等因素对吸附效果的... 详细信息

以赤泥为原料采用焙烧还原-重构法制备层状金属氢氧化物(LDH)和层状金属氧化物(LDO),比较了赤泥、焙烧赤泥、LDO和LDH对活性黄ke-4R染料(ke-4R)、活性艳蓝染料(RBB)的吸附效果;考察了吸附剂用量、吸附温度、吸附时间等因素对吸附效果的影响,并探讨了吸附机理。结果表明:LDH和LDO经XRD测定,证实其具有层状结构;4种吸附剂对ke-4R、RBB的吸附效果排序为:LDO>LDH>赤泥>焙烧赤泥;在投加量0.3g温度30℃,吸附时间90 min时,LDO对50 mg·L^(-1)ke-4R的去除率达到91.1%;在投加量0.1g温度25℃,吸附时间60 min时,LDO对50 mg·L^(-1)RBB的去除率达到97.2%;LDO对ke-4R和RBB的吸附等温方程符合Langmuir型等温式。

关键词：赤泥层状金属氧化物吸附活性黄ke-4R染料活性艳蓝染料