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Distributed active vibration control for helicopter based on diffusion collaboration

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Chinese Journal of Aeronautics 2024年第8期37卷 208-232页

作者： yang YUAN yang LU Xunjun MA Jingliang LI Huiyu YUE National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China Wuhan Second Ship Design and Research Institute Wuhan 430205China

The active vibration control technology has been successfully applied to several helicopter ***,with the increasing of control scale,traditional centralized control algorithms are experiencing significant increase of computational complexity and physical implementation *** address this issue,a diffusion collaboration-based distributed Filtered-x Least Mean Square algorithm applied to active vibration control is proposed,drawing inspiration from the concept of data fusion in wireless sensor *** algorithm distributes the computation load to each node,and constructs the active vibration control network topology of large-scale system by discarding the weak coupling secondary paths between nodes,achieving distributed active vibration *** order to thoroughly validate the effectiveness and superiority of this algorithm,a helicopter fuselage model is designed as the research ***,the excellent vibration reduction performance of the proposed algorithm is confirmed through ***,specialized node control units are developed,which utilize STM32 microcontroller as the processing ***,a distributed control system is constructed based on multi-processor *** on this foundation,a large-scale active vibration control experimental platform is *** on the platform,experiments are carried out,involving the 4-input 4-output system and the 8-input 8-output *** experimental results demonstrate that under steady-state harmonic excitation,the proposed algorithm not only ensures control effectiveness but also reduces computational complexity by 50%,exhibiting faster convergence speed compared with traditional centralized *** time-varying external excitation,the proposed algorithm demonstrates rapid tracking of vibration changes,with vibration amplitudes at all controlled points declining by over 94%,proving the strong robustness and adaptive capability of the algorithm

关键词： Helicopter Active vibration control Diffusion collaboration Distributed control Experiment

Stabilization and detection of labile reaction intermediates in supramolecular containers

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Chinese Chemical Letters 2024年第6期35卷 47-52页

作者： Rui Wang yang Liang Julius Rebek Jr. yang Yu Center for Supramolecular Chemistry&Catalysis and Department of Chemistry College of ScienceShanghai UniversityShanghai 200444China Skaggs Institute for Chemical Biology and Department of Chemistry The Scripps Research InstituteLa JollaCA 92037United States

Detection and observation of reactive intermediates is an essential step in investigation of reaction ***,most reactive intermediates are unstable and present at low concentrations;their short lifetimes make them difficult to detect and *** containers offer opportunities for the stabilization and characterization of those labile species,through isolation from the media and protection inside the cavity of the *** this review,we summarize the examples of labile reaction intermediates that are stabilized and characterized with the help of supramolecular *** container compounds include carcerands,deep cavitands and amide *** focus on unstable guest species-cyclobutadiene,benzocyclopropenone,o-benzyne,1,2,4,6-cycloheptatetraene,anti-Bredt's olefin,fluorophenoxycarbene,O-acylisoamide,and hemiaminalthat act as intermediates in certain organic reactions.

关键词： Supramolecular containers Reaction intermediates Labile species stabilization Short-lived species detection Supramolecular chemistry

Modelling and simulation study on dynamic pollution accumulation process of composite insulator

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High Voltage 2024年第3期9卷 601-613页

作者： Zhongyi yang Dongxiong Liu Xiangjun Zeng Caijin Fan Xin yang Yafei Huang School of Electrical and Information Engineering Changsha University of Science and TechnologyChangshaChina State Key Laboratory of HVDC Electric Power Research InstituteCSGGuangzhouChina

With the widespread application of composite insulators in transmission lines,exploring the accumulation mechanism of pollution particles on composite insulator surfaces is of importance to ensure the safe and steady operation of the power *** the current theoretical shortcomings,this study categorises the accumulation process of particles on the insulator surface into three stages,namely‘spatial motion’,‘surface collision’,and‘surface motion’.The motion and rotation velocities in a multi-physics field are calculated in the spatial motion *** the surface collision stage,a parameter called‘neck height’is introduced to determine the optimum mechanics theory,and the normal deposition criterion is *** the surface motion stage,the sliding displacement and rolling displacement on the surface are calculated based on the rotation speed of the particles.A dynamic pollution accumulation model of the composite insulator is estab-lished based on the normal deposition criterion and tangential ***,numerical simulations are performed by using the finite element *** results show that the proposed model agrees with the actual insulator pollution accu-mulation,and the deposition model is still applicable for various types of composite insulators operating in different applied *** deposition probability of particles increases with the increasing particle *** the surface motion stage,particle displacement increases with particle size and wind velocity.

关键词： composite displacement dynamic

Wintertime Arctic Sea-Ice Decline Related to Multi-Year La Niña Events

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Advances in Atmospheric Sciences 2024年第9期41卷 1680-1690页

作者： Wenxiu ZHONG Qian SHI Qinghua yang Jiping LIU Song yang School of Atmospheric Sciences Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of OceanographyMinistry of Natural ResourcesHangzhou 310012China Guangdong Province Key Laboratory for Climate Change and Natural Disaster Studies Sun Yat-sen UniversityGuangzhou 510275China

Arctic sea ice has undergone a significant decline in the Barents-Kara Sea(BKS)since the late *** studies have shown that the decrease in sea ice caused by increased poleward moisture transport is modulated by tropical sea temperature changes(mainly referring to La Niña events).The occurrence of multi-year La Niña(MYLA)events has increased significantly in recent decades,and their impact on Arctic sea ice needs to be further *** this study,we investigate the relationship between sea-ice variation and different atmospheric diagnostics during MYLA and other La Niña(OTLA)*** decline in BKS sea ice during MYLA winters is significantly stronger than that during OTLA *** is because MYLA events tend to be accompanied by a warm Arctic-cold continent pattern with a barotropic high pressure blocked over the Urals ***,more frequent northward atmospheric rivers intrude into the BKS,intensifying longwave radiation downward to the underlying surface and melting the BKS sea ***,in the early winter of OTLA years,a negative North Atlantic Oscillation presents in the high latitudes of the Northern Hemisphere,which obstructs the atmospheric rivers to the south of *** infer that such a different response of BKS sea-ice decline to different La Niña events is related to stratospheric *** the rapid climate changes in the past,more frequent MYLA events may account for the substantial Arctic sea-ice loss in recent decades.

关键词： Arctic sea ice multi-year ENSO Ural blocking atmospheric river Barents-Kara Sea

Zincophilic Ti_(3)C_(2)Cl_(2)MXene and anti-corrosive Cu NPs for synergistically regulated deposition of dendrite-free Zn metal anode

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Journal of Materials Science & Technology 2024年第2期169卷 137-147页

作者： Yunfei Shen Yi Liu Kaisheng Sun Tiantian Gu Gang Wang Yue yang Jianxiang Pang yang Zheng Xiaodong yang Long Chen Key Laboratory for Green Process of Chemical Engineering of Xinjiang Bingtuan School of Chemistry and Chemical EngineeringShihezi UniversityShihezi 832003China Institute for Chemistry Chemnitz University of TechnologyChemnitz 09107Germany CAS Key Laboratory of Functional Materials and Devices for Special Environments Xinjiang Key Laboratory of Electronic Information Materials and DevicesCenter of Materials Science and Optoelectronics EngineeringXinjiang Technical Institute of Physics and Chemistry of CASUrumqi 830011China Key Laboratory of Ecophysics and Department of Physics College of ScienceShihezi UniversityShihezi 832003China

Dendrites growth,chemical corrosion,and hydrogen evolution reaction(HER)on zinc anodes are the main barriers for the development of aqueous zinc-ion batteries(AZIBs).Constructing interfacial protec-tive layer is an effective way to alleviate the side reactions on the ***,Cu/Ti_(3)C_(2)Cl_(2)MXene(CMX)with high zincophilic and hydrophobic property is prepared by the lewis molten salts etching method,and the CMX interface protection layer is constructed by a simple spin *** CMX coat-ing layer can provide abundant nucleation sites and uniformize the charge distribution through the zin-cophilic Ti_(3)C_(2)Cl_(2)MXene matrix,leading to homogenous Zn *** addition,the hydrophobic coat-ing contained anti-corrosive Cu nanoparticles can prevent the Zn anode from the electrolyte,beneficial for suppressing the chemical corrosion and ***,the stable and reversible Zn plating/stripping is achieved for the Zn anode coated by the CMX,which exhibits the lifespan of over 1400 h at 0.5 mA cm^(−2),and even can steadily run for 700 h with 65 mV at 10 mA cm^(−2).Furthermore,CMX@Zn shows a high coulombic efficiency of over 100%for 3800 cycles,which indicates that the CMX@Zn electrode has excellent stability and reversibility of Zn stripping/*** full batteries assembled with ZnCoMnO/C(ZCM)cathodes also exhibits higher capacity(450.6 mAh g^(−1)at 0.1 A g^(−1))and cycle stability(capacity retention of 70%after 1500 cycles).This work enhanced the lifespan of AZIBs and broaden the research of multifunctional coating layer to other secondary batteries based on metal anodes.

关键词： Zinc anode Spin coating Zincophilic MXene Anti-corrosive Cu NPs Multifunctional coating

Lateral earth pressure of granular backfills on retaining walls with expanded polystyrene geofoam inclusions under limited surcharge loading

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1388-1397页

作者： Kewei Fan Guangqing yang Weilie Zou Zhong Han yang Shen Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing210098China School of Civil Engineering Wuhan UniversityWuhan430072China State Key Laboratory of Mechanical Behavior and System Safety of Traffic Engineering Structures Shijiazhuang Tiedao UniversityShijiazhuang050043China

Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge *** this paper,the failure mode and the earth pressure acting on the rigid retaining wall with EPS geofoam inclusions and granular backfills(henceforth referred to as EPS-wall),under limited surcharge loading are investigated through two-and three-dimensional model *** testing results show that different from the sliding of almost all the backfill in the EPS-wall under semi-infinite surcharge loading,only an approximately triangular backfill slides in the wall under limited surcharge *** distribution of the lateral earth pressure on the EPS-wall under limited surcharge loading is non-linear,and the distribution changes from the increase of the wall depth to the decrease with the increase of the limited surcharge *** approach based on the force equilibrium of a differential element is developed to predict the lateral earth pressure behind the EPS-wall subjected to limited surcharge loading,and its performance was fully validated by the three-dimensional model tests.

关键词： Retaining wall Expanded polystyrene(EPS)geofoam Limited surcharge loading Lateral earth pressure Model test Prediction

Structural optimization design of semi-rigid base asphalt pavement using modulus matching criterion and multi-indicator range analysis

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Journal of Traffic and Transportation Engineering(English Edition) 2024年第1期11卷 131-159页

作者： Zhihao yang Linbing Wang Dongwei Cao Yinghao Miao Hailu yang China Airport Planning&Design Institute Co. Ltd.Beijing 101312China Department of Road and Urban Railway Engineering Beijing University of TechnologyBeijing 100124China National Center for Materials Service Safety University of Science and Technology BeijingBeijing 100083China School of Environmental CivilAgricultural and Mechanical EngineeringUniversity of GeorgiaAthensGA 30602USA China-Road Transportation Verification&Inspection Hi-Tech Co. Ltd.Beijing 100088China

Damage to semi-rigid base asphalt pavement is related to improper matching of the pavement structure *** study mainly focused on the modulus matching of structural layers and the development of a pavement structure optimization ***,the modulus loss of existing pavement structures was analysed,and a three-dimensional finite element model was established based on the existing ***,the influence of the modulus of each structural layer on the mechanical response indicators and fatigue life was *** on the results,a pavement structure design method using the smoothness of the stress-strain curve as the modulus matching criterion of the structural layers was *** it was found that a strain convex point was present and that the stress mutation between the structural layers was significant when the modulus matching of the pavement structure was ***,the evaluation indicators were divided into two groups,namely,mechanical indicators and fatigue life *** it was proposed an optimized pavement structure design method based on modulus matching and multi-indicator range ***,the optimal modulus combination of pavement structure was determined by this *** research systematically studied the influence of the modulus of each structural layer on the mechanical response and fatigue life of the pavement,and proposed the concept and specific executive criteria of modulus matching for the first ***,it also provided an effective optimization method for pavement structure design.

关键词： Stress-strain curve Modulus matching Structural optimization design Multi-indicator range analysis Fatigue life

Inactivation of TGF-βsignaling in CAR-T cells

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Cellular & Molecular Immunology 2024年第3期21卷 309-310页

作者： Zaopeng yang yang-Xin Fu Changping Laboratory Beijing102206China Department of Basic Medical Sciences School of MedicineTsinghua UniversityBeijing100084China

Accumulating evidence suggests that the transforming growth factor(TGF)-βpathway might be an ideal target for optimizing chimeric antigen receptor(CAR)-T-cell therapy for solid *** Cellular&Molecular Immunology,Liang et al.(2024)reported that CAR-T cells expressing SMAD7 displayed favorable antitumor efficacy and a reduced risk of systemic toxicity.

关键词： CAR Immunology

Mineral Geochemistry of Apatite in the Jiama PorphyrySkarn Deposit,Tibet and its Geological Significance

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Acta Geologica Sinica(English Edition) 2024年第2期98卷 399-415页

作者： yang yang TANG Juxing ZHANG Zebin TANG Pan XIE Fuwei RAN Fengqin yang Zongyao yang Huaichao BAI Yun SUN Miao QI Jing School of Earth Sciences Chengdu University of TechnologyChengdu 610059China MNR Key Laboratory of Metallogeny and Mineral Assessment Institute of Mineral ResourcesCAGSBeijing 100037China School of Earth Sciences and Resources China University of GeosciencesBeijing 100083China The Key Laboratory of the Ministry of Education on Solid Waste Treatment and Recycling School of Environment and ResourceSouthwest University of Science and TechnologyMianyangSichuan 621010China Chengdu Surveying Geotechnical Research Institute Co. Ltd.of MCCChengdu 610023China Sichuan Tianfu Mining Investment Co. Ltd.Chengdu 610055China Sichuan Institute of Comprehensive Geological Survey Chengdu 610081China

The Jiama deposit,a significant porphyry-skarn-type copper polymetallic deposit located within the Gangdese metallogenic belt in Tibet,China,exemplifies a typical porphyry metallogenic ***,the mineral chemistry of its accessory minerals remains under-examined,posing challenges for resource assessment and ore *** electron microprobe analysis and LA-ICP-MS analysis,this study investigated the geochemical characteristics of apatite in ore-bearing granite and monzogranite porphyries,as well as granodiorite,quartz diorite,and dark diorite porphyries in the *** also delved into the diagenetic and metallogenic information from these geochemical *** findings include:(1)The SiO_(2) content,rare earth element(REE)contents,and REE partition coefficients of apatite indicate that the dark diorite porphyry possibly does not share a cogenetic magma source with the other four types of porphyries;(2)the volatile F and Cl contents in apatite,along with their ratio,indicate the Jiama deposit,formed in a collisional setting,demonstrates lower Cl/F ratios in apatite than the same type of deposits formed in a subduction environment;(3)compared to non-ore-bearing rock bodies in other deposits formed in a collisional setting,apatite in the Jiama deposit exhibits lower Ce and Ga *** might indicate that rock bodies in the Jiama deposit have higher oxygen ***,the marginal variation in oxygen fugacity between ore-bearing and non-ore-bearing rock bodies within the deposit suggests oxygen fugacity may not serve as the decisive factor in the ore-hosting potential of rock bodies in the Jiama deposit.

关键词： apatite metallogenesis mineral geochemistry porphyry Jiama Tibet