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Adaptive observer-based integral event-triggered antivibration control of a full aircraft active landing gear system with irregular runway excitations

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Science China(Information Sciences) 2024年第6期67卷 248-261页

作者： Wenxiao HU chenglong DU Fanbiao LI Xinmin CHEN Chunhua yang Weihua GUI School of Automation Central South University Research Center in System Engineering for Special Aircrafts Ningbo Institute of Materials Technology and EngineeringChinese Academy of Sciences

This study addresses the antivibration issue of a full aircraft active landing gear system(LGS)under landing impact and runway excitations via a novel adaptive observer-based integral event-triggered control method. First, a full aircraft active LGS comprising a front gear and two synchronized main left and right gears with active suspensions is established, where the information exchange among them is not implemented directly. Second, two adaptive observers are designed separately for the front and main LGSs to identify the varying damping parameters and estimate the system states simultaneously. Third, estimated states are transmitted to a shared network through a novel integral event-triggered mechanism(I-ETM);thus, the front and main LGSs are interconnected, and a networked control scheme for the aircraft LGS is constructed. Additionally, the integrated active control law is designed with the aid of the transmitted states of the front and main LGSs, enhancing the robustness against the pitch vibration of the ***, the L2-stability of the hybrid system is guaranteed to depress the vertical vibration effect of the landing impact and irregular runway excitations, thus improving passenger safety and comfort. Moreover,a codesign method is provided to obtain feasible solutions to the gain matrices of the observers and controllers simultaneously. Simulation and comparison results are presented to illustrate the effectiveness and superiority of the proposed control scheme in antivibration and saving communication resources.

关键词： aircraft active landing gear antivibration control integral event-triggered mechanism adaptive observer ${\mathcal{L}}_2$-stability

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1990~2019年中国非风湿性瓣膜性心脏病疾病负担及变化趋势分析

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中国循环杂志 2024年第8期39卷 806-812页

作者：胡守财陶堰成马浩天杨成龙赵国辉江伊鹏胡尕伟李庆新甘肃中医药大学第一临床医学院兰州730000 中国人民解放军联勤保障部队第九四○医院普胸外科兰州730050

目的:分析1990~2019年中国非风湿性瓣膜性心脏病(non-rheumatic valvuiar heart disease,NRVHD)疾病负担及变化趋势。方法:基于2019年全球疾病负担数据库收集1990~2019年中国NRVHD相关数据,分析这一时期NRVHD的粗发病率、粗患病率、粗... 详细信息

目的:分析1990~2019年中国非风湿性瓣膜性心脏病(non-rheumatic valvuiar heart disease,NRVHD)疾病负担及变化趋势。方法:基于2019年全球疾病负担数据库收集1990~2019年中国NRVHD相关数据,分析这一时期NRVHD的粗发病率、粗患病率、粗伤残调整寿命年(DALY)及其年龄标化率等数据,并通过Joinpoint回归模型分析相应的变化趋势。利用灰色预测模型GM(1,1)预测2020~2029年中国NRVHD负担状况。结果:中国NRVHD粗发病率、粗患病率和粗DALY率从1990年的7.87/10万、123.21/10万和9.83/10万上升到2019年的22.85/10万、374.16/10万和11.95/10万;年龄标化发病率、年龄标化患病率从1990年的9.22/10万、169.04/10万上升到2019年的15.30/10万、262.85/10万,女性均高于男性;年龄标化DALY率从1990年的13.43/10万下降到2019年的9.07/10万,女性均高于男性。Joinpoint回归模型分析显示,年龄标化发病率、年龄标化患病率呈上升趋势,年龄标化DALY率呈下降趋势[平均年度变化百分比(AAPC)分别为1.86%、1.72%和-1.66%],变化趋势有统计学意义(P均<0.05)。1990~2019年不同年龄组人群的疾病负担整体呈上升趋势,其粗发病率、粗患病率及粗DALY率均随着年龄的增长而升高,60岁以上的老年人群是疾病负担的主要群体。灰色预测模型GM(1,1)结果显示,至2029年年龄标化发病率和年龄标化患病率分别增加到18.51/10万、303.26/10万,年龄标化DALY率下降到7.42/10万。结论:1990~2019年中国NRVHD的年龄标化发病率、年龄标化患病率呈上升趋势,年龄标化DALY率均呈下降趋势。NRVHD的疾病负担仍然较重,女性和高龄人群尤其需要关注。

关键词：非风湿性瓣膜性心脏病疾病负担变化趋势 Joinpoint模型中国

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Chartrenoline, a novel alkaloid isolated from a marine Streptomyces chartreusis NA02069

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Chinese Chemical Letters 2019年第1期30卷 44-46页

作者： Chengli Liu chenglong yang Yingjie Zeng Jing Shi Lingyu Li Wei Li Ruihua Jiao Renxiang Tan Huiming Ge State Key Laboratory of Pharmaceutical Biotechnology Institute of Functional Biomolecues School of Life Sciences Nanjing University

A novel alkaloid, chartrenoline(1), featuring an unusual 6/6/5/5-tetracyclic nucleus, was isolated from a marine Streptomyces chartreusis NA02069. The structure of 1 including its absolute configurations was established by extensive analyses of its high resolution mass, NMR and single-crystal X-ray diffraction data. A plausible biosynthetic pathway for chartrenoline(1) is proposed.

关键词： Alkaloid Chartrenoline Streptomyces chartreusis 6/6/5/5-Tetracyclic nucleus Marine-derived microorganism

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Evolution of Biofilm and Its Effect on Microstructure of Mortar Surfaces in Simulated Seawater

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Journal of Wuhan University of Technology(Materials Science) 2024年第1期39卷 234-243页

作者：荣辉 YU chenglong 张颖 School of Materials Science and Engineering Tianjin Chengjian UniversityTianjin 300384China Tianjin Key Laboratory of Building Green Functional Materials Tianjin Chengjian UniversityTianjin 300384China

To explore the role of biofilm formation on the corrosion of marine concrete structures, we investigated the attachment of biofilm on mortar surfaces in simulated seawater and the influence of biofilm on the microstructure of mortar surfaces. The results show that the evolution of biofilm on mortar surfaces in simulated seawater is closely related to the corrosion suffered by the mortar, and the process of biofilm attachment and shedding is continuous and cyclical. It is found that the specimens in the absence of biofilm attachment are more severely eroded internally by the corrosive medium in simulated seawater than those in the presence of biofilm attachment. For the specimens without biofilm attachment, after 60 days, gypsum forms,and after 120 days, the number of pores in the mortar is reduced. In contrast, for the specimens in the presence of biofilm attachment, gypsum could only be detected after 90 days, and fewer pores are filled. Therefore, the formation of biofilm could delay the invasion of the corrosive medium into the interior of mortar during the evolution of biofilm on mortar surfaces, mitigating the corrosion of mortars in seawater.

关键词： biofilm attachment mortar sulfur-oxidizing bacteria gypsum simulated seawater microstructure

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Shaping the Spatial Coherence of Quantum Source

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Chinese Physics Letters 2024年第9期41卷 38-39页

作者： chenglong You Quantum Photonics Laboratory Department of Physics and AstronomyLouisiana State UniversityBaton RougeLouisiana 70803USA

There has been immense research interest in quantum entanglement due to its ability to generate stronger-thanclassical nonlocal correlations.^([1,2])These strong,nonlocal correlations form the backbone of various quantum information *** of the core principles of quantum entanglement is quantum coherence,which provides deep insights into the statistical correlations among quantum particles.^([3–5])Quantum coherence reflects the wavelike properties of quantum particles,enabling them to exhibit interference and unique quantum behaviors.

关键词： particles. quantum backbone

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Coordination environments build up and tune a superior synergistic “genome” toward novel trifunctional (TM-N_(x)O_(4−x))@g- C_(16)N_(3)-H_(3): High-throughput inspection of ultra-high activity for water splitting and oxygen reduction reactions

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Nano Research 2024年第4期17卷 2337-2351页

作者： Chunyao Fang Xian Wang Qiang Zhang Xihang Zhang chenglong Shi Jingcheng Xu Mengyu yang Department of Physics University of Shanghai for Science and TechnologyShanghai 200093China School of Materials and Chemistry University of Shanghai for Science and TechnologyShanghai 200093China

Emerging as a prominent area of focus in energy conversion and storage technologies,the development of highly active metal-based single-atom catalysts(SACs)holds great signiﬁcance in searching alternatives to replace precious metals toward the efficient,stable,and low-cost hydrogen evolution reaction(HER),as well as the oxygen evolution reaction(OER)and the oxygen reduction reaction(ORR).Combining the tremendous tunability of ligand and coordination environment with rich metal-based electrocatalysts can create breakthrough opportunities for achieving both high stability and ***,we propose a novel and stable holey graphene-like carbon nitride monolayer g-C_(16)N5(N_(4)@g-C_(16)N_(3))stoichiometries interestingly behaving as a natural substrate for constructing SACs((TM-N_(4))@g-C_(16)N_(3)),whose evenly distributed holes map rich and uniform nitrogen coordination positions with electron-rich lone pairs for anchoring transition metal(TM)***,we employed density functional theory(DFT)calculations to systematically investigate the electrocatalytic activity of(TM-N_(4))@g-C_(16)N_(3) toward HER/OER/ORR,meanwhile considering the synergistic modulation of H-loading and O-coordination((TM-N_(x)O_(4-x))@g-C_(16)N_(3)^(-)H_(3),x=0–4).Together a“four-step procedure”screening mechanism with the first-principles high-throughput calculations,we find that(Rh-N_(4))and(Ir-N_(2)O_(2)-II)distributed on g-C_(16)N_(3)^(-)H_(3) can modulate the adsorption strength of the adsorbates,thus achieving the best HER/OER/ORR performance among 216 candidates,and the lowest overpotential of 0.098/0.3/0.46 V and 0.06/0.48/0.45 V,***,the d-band center,crystal orbital Hamilton population(COHP),and molecular orbitals are used to reveal the OER/ORR activity ***,the Rh/Ir-d orbital is dramatically hybridized with the O-p orbital of the oxygenated adsorbates,so that the lone-electrons incipiently locate at the antibonding orbital pair up and popula

关键词： single atom catalysts loading and coordination hydrogen evolution reaction oxygen evolution reaction oxygen reduction reaction

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石墨烯改性环氧富锌底漆拉开法附着力试验影响因素分析

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上海涂料 2024年第2期62卷 41-44页

作者：张东晋川孙庆华黄选民杨成龙冯琛玉国营川西机器厂四川成都611937

对石墨烯环氧富锌底漆拉开法附着力进行测试,分析了试样组合方式、喷涂压力、胶黏剂和试柱材质的选择对试验结果的影响。结果表明:当选择测量不确度定最小的双面试柱试样组合、喷涂压力为0.3 MPa、HY-914环氧胶黏剂和钢试柱时,可保证试... 详细信息

对石墨烯环氧富锌底漆拉开法附着力进行测试,分析了试样组合方式、喷涂压力、胶黏剂和试柱材质的选择对试验结果的影响。结果表明:当选择测量不确度定最小的双面试柱试样组合、喷涂压力为0.3 MPa、HY-914环氧胶黏剂和钢试柱时,可保证试验结果的可靠性高,数据波动小。

关键词：涂层拉开法附着力试柱试验

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Research on Electromagnetic Acoustic Emission Signal Recognition Based on Local Mean Decomposition and Least Squares Support Vector Machine

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Journal of Computer and Communications 2023年第5期11卷 70-83页

作者： chenglong yang Yushu Lai Qiuyue Li School of Electronic and Information Engineering Chongqing Three Gorges University Chongqing China Chongqing Engineering Technology Research Center for Light Alloy and Processing Chongqing China

Electromagnetic acoustic emission technology is one of nondestructive testing, which can be used for defect detection of metal specimens. In this study, round and cracked metal specimens, round metal specimens, and intact metal specimens were prepared. And the electromagnetic acoustic emission signals of the three specimens were collected. In addition, the local mean decomposition(LMD), Autoregressive model(AR model) and least squares support vector machine (LSSVM) algorithms were combined to identify the eletromagnetic acoustic emission signals of round and cracked, round, and intact specimens. According to the algorithm recognition results, the recognition accuracy of can reach above 97.5%, which has a higher recognition rate compared with SVM and BP neural network. The results of the study show that the algorithm is able to identify quickly and accurately crack defect in metal specimens.

关键词： Electromagnetic Acoustic Emission Technology LMD LSSVM Defect Detection of Metal Crack

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Differentiated self-assembly through orthogonal noncovalent interactions towards the synthesis of two-dimensional woven supramolecular polymers

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Chinese Chemical Letters 2024年第5期35卷 179-182页

作者： Zhenzhu Wang chenglong Liu Yunpeng Ge Wencan Li Chenyang Zhang Bing yang Shizhong Mao Zeyuan Dong State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Center for Supramolecular Chemical Biology Jilin UniversityChangchun 130012China

Molecular weaving is a powerful approach to make molecularly woven materials that have showed unprecedented characteristics and properties intrinsically distinct to those of non-woven *** here report a facile and efficient approach for the synthesis of 2D woven supramolecular polymers by differentiated self-assembly through orthogonal noncovalent ***,the difference in binding strength of two orthogonal noncovalent interactions can be used to control the process of molecular ***,single-layered 2D woven supramolecular polymers were synthesized and fully characterized by various *** study demonstrates a controllable method for molecular weaving,and will significantly hasten the development of molecularly woven materials.

关键词： Differentiated self-assembly Double-stranded helix Molecular weaving Supramolecular chemistry Two-dimensional polymer

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Microwave-Assisted Confining Growth and Liquid Exfoliation of sp3-Hybrid Carbon Nitride Nano/Micro-Crystals

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ENERGY & ENVIRONMENTAL MATERIALS 2024年第6期7卷 399-408页

作者： Shen, chenglong Lou, Qing Liu, Kaikai Zheng, Guangsong Song, Runwei Zang, Jinhao yang, Xigui Li, Xing Dong, Lin Shan, Chongxin Zhengzhou Univ Minist Educ Sch Phys & Lab Zhongyuan Light Henan Key Lab Diamond Optoelect Mat & DevicesKey Zhengzhou 450052 Peoples R China

As one promising carbon-based material, sp(3)-hybrid carbon nitride has been predicted with various novel physicochemical properties. However, the synthesis of sp(3)-hybrid carbon nitride is still limited by the nanaoscale, low crystallinity, complex source, and expensive instruments. Herein, we have presented a facile approach to the sp(3)-hybrid carbon nitride nano/micro-crystals with microwave-assisted confining growth and liquid exfoliation. Actually, the carbon nitride nano/micro-crystals can spontaneously emerge and grow in the microwave-assisted polymerization of citric acid and urea, and the liquid exfoliation can break the bulk disorder polymer to retrieve the highly crystalline carbon nitride nano/micro-crystals. The obtained carbon nitride nano/micro-crystals present superior blue light absorption strength and surprising photoluminescence quantum yields of 57.96% in ethanol and 18.05% in solid state. The experimental characterizations and density functional theory calculations reveal that the interface-trapped localized exciton may contribute to the excellent intrinsic light emission capability of carbon nitride nano/micro-crystals and the interparticle staggered stacking will prevent the aggregation-caused-quenching partially. Finally, the carbon nitride nano/micro-crystals are demonstrated to be potentially useful as the phosphor medium in light-emitting-diode for interrupting blue light-induced eye damage. This work paves new light on the synthesis strategy of sp(3)-hybrid carbon nitride materials and thus may push forward the development of multiple carbon nitride research.

关键词： confining growth density functional theory liquid exfoliation luminescence sp(3)-hybrid carbon nitride BETA-C3N4 FLUORESCENT FILMS NANODOTS DRIVEN ROUTE DOTS CNX

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