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Refiector Deformation Measurement and Correction Methodology of Large Antenna Based on Phased Array Feed

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Research in Astronomy and Astrophysics 2024年第3期24卷 297-308页

作者： Zan Wang De-Qing kong hong-Bo Zhang Yan Su Xin-Ying Zhu Cong-Si Wang Yu-Chen Liu Key Laboratory of Lunar and Deep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China university of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Electronic Equipment Structure Design Ministry of EducationXidian UniversityXi'an 710071China

To solve the problem of time-consuming measurement and correction of large antennas’reflector deformation,a new microwave holography methodology based on a Phased Array Feed(PAF)is *** from the known expression of receiving signals in microwave holography,the theory of PAF holography is derived through Geometrical *** deformation,as well as pointing deviation and subreflector offset,can be calculated out by applying the derived equations.A measurement and correction system based on PAF holography is depicted,and two kinds of measurement methods are *** proposed measurement methodology is verified by numerical simulation,and its measurement error is *** results indicate that our proposed methodology is feasible,especially for Cassegrain antennas.

关键词： telescopes-methods analytical--methods numerical

Large-area ultrastrong and stiff aramid nanofiber based layered nanocomposite films

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Nano Research 2024年第2期17卷 829-835页

作者： Zhidong Nie Yingzhi Sun Tianxu Zhou Shengwen kong Linxing Liu Chuangqi Zhao Mingjie Liu Key Laboratory of Bioinspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeihang UniversityBeijing 100191China university of Science and Technology of china Hefei 230026China Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China International Research Institute for Multidisciplinary Science Beihang UniversityBeijing 100191China

One-dimensional(1D)aramid nanofiber(ANF)based nanocomposite films have drawn increasing attentions in various applications due to their excellent mechanical properties and impressive chemical and thermal ***,the large-area fabrication of aramid nanocomposite films with ultrastrong mechanical properties under mild conditions remains a great *** we present a facile superspreading-assisted strategy to produce aramid nanofiber based oriented layered nanocomposites using phase inversion process that occurs at the fully swollen hydrogel *** nanocomposite films based on ANF,carboxylation carbon tube(CNT–COOH),poly(vinyl alcohol)(PVA),and MXene nanosheet exhibit a tensile strength of up to 870.8±85 MPa,a Young’s modulus of 2..8±2.2.GPa,and outstanding toughness(up to 43.2.4.6 MJ/m^(3)),which are much better than those conventional aramid nanofiber based *** conductivity of our nanocomposite films reaches the maximum of about 1100 S/*** fabulous mechanical properties combination and continuous production capability render our strategy representing a promising direction for the development of high-performance nanocomposites.

关键词： aramid nanofibers MXene nanosheets nanocomposites ultrastrong and stiff superspreading large-area production

Defect spinel oxides for electrocatalytic reduction reactions

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Nano Research 2024年第5期17卷 3547-3570页

作者： Zhijuan Liu Jinyu Guo Lu-yu Liu Fen Wang Zhijie kong Yanyong Wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsKey Laboratory of Special Environmental Functional Materials(Zhengzhou University)Ministry of EducationGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Electrocatalytic reduction reactions play a crucial role in electrochemical energy conversion and storage technology,which are emerging technologies to ameliorate environmental *** oxides are widely explored in electrocatalytic oxidation reactions but have a poor intrinsic ability to reduction reactions,making their electrocatalytic ability less *** improve this,defect engineering is a valuable method for regulating the electronic structure and coordination ***,this manuscript discusses the use of defect spinel oxides in electrocatalytic reduction reactions,including the different types of defects,construction methods,and characterization *** also outlines the various applications of defect spinel oxides in different electrocatalytic reduction ***,it goes over the challenges and future outlooks for defect *** review aims to thoroughly explain how defect spinels work in electrocatalytic reduction reactions and serve as a helpful guide for creating effective electrocatalysts.

关键词： defect spinel oxides electrochemical reduction reactions electrocatalytic mechanism dynamic evolution

Biotoxicity dynamic change and key toxic organics identification of coal chemical wastewater along a novel full-scale treatment process

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Journal of Environmental Sciences 2024年第4期138卷 277-287页

作者： Weiwei Ma Xiaoqi Zhang hongjun Han Xueqing Shi Qiaoping kong Tong Yu Fei Zhao School of Environmental and Municipal Engineering Qingdao University of TechnologyQingdao 266520China State Key Laboratory of Urban Water Resource and Environment Harbin Institute of TechnologyHarbin 150090China

It is particularly important to comprehensively assess the biotoxicity variation of industrial wastewater along the treatment process for ensuring the water environment ***,intensive studies on the biotoxicity reduction of industrial wastewater are still *** this study,the toxic organics removal and biotoxicity reduction of coal chemical wastewater(CCW)along a novel full-scale treatment process based on the pretreatment process-anaerobic process-biological enhanced(BE)process-anoxic/oxic(A/O)process-advanced treatment process was *** process performed great removal efficiency of COD,total phenol,NH_(4)^(+)-N and total *** the biotoxicity variation along the treatment units was analyzed from the perspective of acute biotoxicity,genotixicity and oxidative *** results indicated that the effluent of pretreatment process presented relatively high acute biotoxicity to Tetrahymena *** the acute biotoxicity was significantly reduced in BE-A/O *** the genotoxicity and oxidative damage to Tetrahymena thermophila were significantly decreased after advanced *** polar organics in CCW were identified as the main biotoxicity *** were positively correlated with acute biotoxicity,while the nitrogenous heterocyclic compounds and polycyclic aromatic hydrocarbons were positively correlated with *** the biotoxicity was effectively reduced in the novel full-scale treatment process,the effluent still performed potential biotoxicity,which need to be further explored in order to reduce environmental risk.

关键词： Acute biotoxicity Genotoxicity Oxidative damage Toxic organics Coal chemical wastewater Novel full-scale treatment process

Abundance and sources of particulate polycyclic aromatic hydrocarbons and aromatic acids at an urban site in central china

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Journal of Environmental Sciences 2024年第8期142卷 155-168页

作者： Luqi Shang Zhe Dong Zihan Li Mingkai Wang Zihan kong Xiao Li Ruiqin Zhang School of Ecology and Environment Zhengzhou UniversityZhengzhou 450001China College of Chemistry Zhengzhou UniversityZhengzhou 450001China Institute of Environmental Sciences Zhengzhou UniversityZhengzhou 450001China

We conducted a simultaneous field study of PM_(2.5)-bound particulate polycyclic aromatic hydrocarbons(PAHs)and aromatic acids(AAs)in a polluted city Zhengzhou to explore the concentration,sources and potential conversion pathways between PAHs and AAs in different *** average concentrations of PM_(2.5),2.PAHs and 8AAs during the sampling period were 77μg/m^(3),75 ng/m^(3),and 2.3 ng/m^(3),*** concentration of both2.PAHs and 8AAs were highest in winter and lowest in summer with ratios of 6.3 and 2.3,*** with 5-7 rings were the main components of PAHs(52.),followed by 4rings PAHs(30%)and 2.3 rings PAHs(18%).According to the source appointment results obtained by positive matrix factorization,the main sources of PAHs were combustion and vehicle emissions,which account for 37%and 34%,respectively.8AAs were divided into three groups,including four benzene dicarboxylic acids(B2.As),three benzene tricarboxylic acids(B3CAs)and one benzene tetracarboxylic acid(B4CA).And interspecies correlation analysis with PM_(2.5)source markers were used to investigate potential *** acid(o-Ph)was the most abundant specie of 8AAs(157 ng/m^(3),55%of 8AAs),which was well correlated with ***,B3CAs and B4CA were highly correlated with sulfate and weakly correlated with levoglucosan,suggesting that secondary formation was their main *** logical oxidation products of PAHs,o-Ph and B3CAs showed good correlations with a number of PAHs,indicating possible photochemical oxidation pathway by *** addition,O_(3),NO_(2.,temperature and relative humidity have positive effects on the secondary formation of B3CAs.

关键词： Polycyclic aromatic hydrocarbons Aromatic acids Source appointment Secondary formation

An electromagnetic semi-active dynamic vibration absorber for thin-walled workpiece vibration suppression in mirror milling

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Applied mathematics and Mechanics(English Edition) 2024年第8期45卷 1315-1334页

作者： Jianghua kong Bei DING Wei WANG Zhixia WANG Juliang XIAO hongyun QIU School of Mechanical Engineering Tianjin UniversityTianjin 300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin 300350China Key Laboratory of Modern Mechanisms and Equipment Design of the State Ministry of Education Tianjin UniversityTianjin 300350China

As critical components of aircraft skins and rocket fuel storage tank shells,large thin-walled workpieces are susceptible to vibration and deformation during machining due to their weak local *** address these challenges,we propose a novel tunable electromagnetic semi-active dynamic vibration absorber(ESADVA),which integrates with a magnetic suction follower to form a followed ESADVA(follow-ESADVA)for mirror *** system combines a tunable magnet oscillator with a follower,enabling real-time vibration absorption and condition feedback throughout the milling ***,the device supports self-sensing and frequency adjustment by providing feedback to a linear actuator,which alters the distance between *** resolves the traditional issue of being unable to directly monitor vibration at the machining point due to space constraints and tool *** frequency shift characteristics and vibration absorption performance are comprehensively *** and experimental results demonstrate that the prototyped follow-ESADVA achieves frequency synchronization with the milling tool,resulting in a vibration suppression rate of approximately 47.57%.Moreover,the roughness of the machined surface decreases by18.95%,significantly enhancing the surface *** results of this work pave the way for higher-quality machined surfaces and a more stable mirror milling process.

关键词： semi-active dynamic vibration absorber(SADVA) mirror milling selfsensing vibration absorption tuning thin-walled workpiece

ATM Activation is Key in Vasculogenic Mimicry Formation by Glioma Stem-like Cells

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Biomedical and Environmental Sciences 2024年第8期37卷 834-849页

作者： Jing Xie Jiaxin Tang Yuan Li Xue kong Wei Wang Haibo Wu Department of Pathology the First Affiliated Hospital of USTCDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230036AnhuiChina Intelligent Pathology Institute Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230036AnhuiChina

Objective Vasculogenic mimicry(VM)is a novel vasculogenic process integral to glioma stem cells(GSCs)in glioblastoma(GBM).However,the relationship between VM and ataxia-telangiectasia mutated(ATM)serine/threonine kinase activation,which confers chemoradiotherapy resistance,remains *** We investigated VM formation and phosphorylated ATM(pATM)levels by CD31/GFAPperiodic acid-Schiff dual staining and immunohistochemical staining in 145 GBM *** stem-like cells(GSLCs)derived from the formatted spheres of U87 and U2.1 cell lines and their pATM level and VM formation ability were examined using western blot and three-dimensional *** the examination of the function of pATM in VM formation by GSLCs,ATM knockdown by shRNAs and deactivated via ATM phosphorylation inhibitor KU55933 were *** VM and high pATM expression occurred in 38.5% and 41.8% of tumors,respectively,and were significantly associated with reduced progression-free and overall *** with VM-positive GBMs exhibited higher pATM levels(r_(s)=0.42.,P=0.01).The multivariate analysis established VM as an independent negative prognostic factor(P=0.002..Furthermore,GSLCs expressed high levels of pATM and formed vascular-like networks in *** inactivation or knockdown hindered VM-like network formation concomitant with the downregulation of pVEGFR-2.VE-cadherin,and laminin *** VM may predict a poor GBM prognosis and is associated with pATM *** propose that pATM promotes VM through extracellular matrix modulation and VE-Cadherin/pVEGFR-2.activation,thereby highlighting ATM activation as a potential target for enhancing anti-angiogenesis therapies for GBM.

关键词： Glioblastoma Vasculogenic mimicry Ataxia-telangiectasia mutated(ATM) Glioma stem-like cell

Force Compensation Control for Electro-Hydraulic Servo System with Pump-Valve Compound Drive via QFT-DTOC

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 228-246页

作者： Kaixian Ba Yuan Wang Xiaolong He Chunyu Wang Bin Yu Yaliang Liu Xiangdong kong Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Qinhuangdao 066004China School of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China National Engineering Research Center for Local Joint of Advanced Manufacturing Technology and Equipment Yanshan UniversityQinhuangdao 066004China

Each joint of a hydraulic-driven legged robot adopts a highly integrated hydraulic drive unit(HDU),which features a high power-weight ***,most HDUs are throttling-valve-controlled cylinder systems,which exhibit high energy *** contrast,pump control systems offer a high ***,their response ability is *** fully utilize the advantages of pump and valve control systems,in this study,a new type of pump-valve compound drive system(PCDS)is designed,which can not only effectively reduce the energy loss,but can also ensure the response speed and response accuracy of the HDUs in robot joints to satisfy the performance requirements of ***,considering the force control requirements of energy conservation,high precision,and fast response of the robot joint HDU,a nonlinear mathematical model of the PCDS force control system is first *** addition,pressure-flow nonlinearity,friction nonlinearity,load complexity and variability,and other factors affecting the system are considered,and a novel force control method based on quantitative feedback theory(QFT)and a disturbance torque observer(DTO)is designed,which is denoted as QFT-DTOC *** method improves the control accuracy and robustness of the force control system,reduces the effect of the disturbance torque on the control performance of the servo motor,and improves the overall force control performance of the ***,experimental verification is performed using the PCDS performance test *** experimental results and quantitative data show that the QFT-DTOC proposed herein can significantly improve the force control performance of the *** relevant force control method can be used as a bottom-control method for the hydraulic servo system to provide a foundation for implementing the top-level trajectory planning of the robot.

关键词： Legged robot Pump-valve compound drive system(PCDS) Force compensation control Quantitative feedback theory(QFT) Disturbance torque observer(DTO)

Heat transfer enhanced inorganic phase change material compositing carbon nanotubes for battery thermal management and thermal runaway propagation mitigation

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Journal of Energy Chemistry 2024年第2期89卷 226-238,I0006页

作者： Xinyi Dai Ping Ping Depeng kong Xinzeng Gao Yue Zhang Gongquan Wang Rongqi Peng Center for Offshore Engineering and Safety Technology China University of Petroleum(East China)Qingdao 266580ShandongChina College of Chemistry and Chemical Engineering China University of Petroleum(East China)Qingdao 266580ShandongChina

Developing technologies that can be applied simultaneously in battery thermal management(BTM)and thermal runaway(TR)mitigation is significant to improving the safety of lithium-ion battery *** phase change material(PCM)with nonflammability has the potential to achieve this dual *** study proposed an encapsulated inorganic phase change material(EPCM)with a heat transfer enhancement for battery systems,where Na_(2.HPO_(4)·12._(2.O was used as the core PCM encapsulated by silica and the additive of carbon nanotube(CNT)was applied to enhance the thermal *** microstructure and thermal properties of the EPCM/CNT were analyzed by a series of characterization *** different incorporating methods of CNT were compared and the proper CNT adding amount was also *** preparation,the battery thermal management performance and TR propagation mitigation effects of EPCM/CNT were further investigated on the battery *** experimental results of thermal management tests showed that EPCM/CNT not only slowed down the temperature rising of the module but also improved the temperature uniformity during normal *** peak battery temperature decreased from 76℃to 61.2.at 2.C discharge rate and the temperature difference was controlled below 3℃.Moreover,the results of TR propagation tests demonstrated that nonflammable EPCM/CNT with good heat absorption could work as a TR barrier,which exhibited effective mitigation on TR and TR *** trigger time of three cells was successfully delayed by 12.,474 and 551 s,respectively and the propagation intervals were greatly extended as well.

关键词： Inorganic phase change material Carbon nanotube Battery thermal management Thermal runaway propagation Fire resistance Encapsulation