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Modulating sparks in a pulse train for repetitive and energy efficient plasma generation

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High Voltage 2023年第6期8卷 1168-1179页

作者： bo Yin Yifei Zhu yun Wu Institute of Aero‐Engine School of Mechanical EngineeringXi'an Jiaotong UniversityXi'anChina School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina Science and Technology of Plasma Dynamics Laboratory Airforce Engineering UniversityXi'anChina

Spark is a widely studied plasma source for active species production;however,it ex-periences unstable transitions(*** a thermal arc)at high frequencies or long pulse *** this study,the sparks generated in a pulse train were studied and modulated based on a physics‐corrected deep learning *** results show that a highly repeatable and stable spark plasma source can be achieved by automatically adjusting the voltage amplitude according to the discharge frequency in a high‐frequency pulse train within the time scale of the fluid *** influences of the electron number density increasing mode and modulated driven voltage profiles on the energy efficiencies were also studied.

关键词： Spark pulse energy

Heat engines of the Kerr-AdS black hole

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Communications in Theoretical Physics 2023年第12期75卷 129-137页

作者： Yi zhong yun-Zhi Du School of Physics and Electronics Hunan UniversityChangsha 410082China Department of Physics Shanxi Datong UniversityDatong 037009China Institute of Theoretical Physics Shanxi Datong UniversityDatong 037009China

In this paper,we investigate three types of heat engines for the rotating Kerr-Anti de Sitter(Kerr-AdS)black *** first briefly review the thermodynamics and phase structure of the Kerr-AdS black hole and obtain the phase structure in the T-S *** thermal stability of Kerr-AdS black holes,along with their dependence on various parameters,is thoroughly ***,by utilizing the phase diagram,we consider three types of heat engines:the maximal Carnot engine,Stirling engine,and Rankine *** calculate both the work and efficiency for these *** results indicate that angular momentum has a significant influence on these heat engines.

关键词： black hole heat engine Kerr-AdS

Numerical simulation of pollution process due to resuspension of bed materials adsorbing pollutants in alluvial rivers

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Science China(Technological Sciences) 2015年第7期58卷 1280-1288页

作者： DING yun XIAO Yang zhong DeYu State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University College of Water Conservancy and Hydropower Engineering Hohai University State Key Laboratory of Hydroscience and Engineering Tsinghua University

Resuspension of bed materials absorbing pollutants potentially poses unpredictable challenges to water management in alluvial rivers and its mechanism of transport has not been widely *** this study,a transport equation that defines the movement of pollutants adsorbed on the bed materials in the active bed layer is established,on the basis of mass conservation law and continuum *** transport equation is coupled into the 1-D mathematical model to numerically investigate water pollution process due to the scour of the bed sediment adsorbing *** with the situation in which the dynamics of the active bed layer is not considered indicate that the periodical evolution of the bed layer plays an innegligible role in the pollution process due to sediment ***,comparisons of the results with available experimental observations are presented,and fairly good agreement is obtained.

关键词： resuspension pollutants alluvial rivers active bed layer

Quantum secure direct communication with hybrid entanglement

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Frontiers of physics 2024年第5期19卷 241-253页

作者： Peng Zhao Wei zhong Ming-Ming Du Xi-yun Li Lan Zhou Yu-bo Sheng College of Electronic and Optical Engineering&College of Flexible Electronics(Future Technology) Nanjing University of Posts and TelecommunicationsNanjing 210023China Institute of Quantum Information and Technology Nanjing University of Posts and TelecommunicationsNanjing 210003China College of Science Nanjing University of Posts and TelecommunicationsNanjing 210023China

Quantum secure direct communication(QSDC)can transmit secret messages without keys,making it an important branch of quantum *** present a hybrid entanglement-based quantum secure direct communication(HE-QSDC)protocol with simple linear optical elements,combining the benefits of both continuous variables(CV)and discrete variables(DV)*** analyze the security and find that the QSDC protocol has a positive security capacity when the bit error rate is less than *** with previous DV QSDC protocols,our protocol has higher communication efficiency due to performing nearly deterministic Bell-state *** the other hand,compared with CV QSDC protocol,this protocol has higher fidelity with largeα.Based on these advantages,our protocol may provide an alternative approach to realize secure communication.

关键词： quantum secure direct communication hybrid entanglement Bell-state measurement

Annealing Effect on Wear Resistance of Nanostructured 316L Stainless Steel Subjected to Dynamic Plastic Deformation

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Journal of Materials Science & Technology 2012年第10期28卷 871-877页

作者： bo Wang Bin Yao zhong Han Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

Bulk nanostructured 316L austenitic stainless steel （SS） samples with nano-scale twin bundles embedded in nano-sized grains were synthesized by using dynamic plastic deformation （DPD）. Subsequent thermal an-nealing of the as-DPD sample leads to a single austenitic structure with static recrystallized （SRX） grains in nanostructured matrix. Oil-lubricated sliding tests of ball-on-disc type were carried out for the as-DPD and the as-annealed DPD steel samples in comparison with coarse grained （CG） steel samples. Experimental results show that the as-DPD 316L steel exhibits a little enhanced wear resistance under a load of 10 N, and nearly identical wear resistance under a load of 30 N relative to that of the CG sample. After annealing, the wear resistance roughly follows the Archard equation under a load of 10 N. However, the wear resistance increases with increasing hardness, and decreases with a further increase in hardness under a load of 30 N. The highest wear resistance can be found in the DPD sample annealed at 750 ℃ for about 20 min, which is more than 46% higher than that of the CG steel sample. This phenomenon is originated from the microstructure with an optimized combination of strength and ductility as a result of moderate plastic deformation in SRX grained regions.

关键词： Nanostructrued metals Stainless steel Wear resistance Annealing Subsurfacemicrostructure

Green Monomer of CO_(2) and Alkyne-based Four-component Tandem Polymerization toward Regio-and Stereoregular Poly(aminoacrylate)s

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Chinese Journal of Polymer Science 2021年第1期39卷 51-59,I0006页

作者： bo Song An-Jun Qin Ben zhong Tang State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesCenter for Aggregation-Induced EmissionSouth China University of TechnologyGuangzhou 510640China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Centre for Tissue Restoration and ReconstructionInstitute for Advanced StudyDepartment of Chemical and Biological EngineeringThe Hong Kong University of Science&TechnologyHong KongChina

Green monomers, such as carbon dioxide(CO_(2)), are closely related to our daily life and highly desirable to be transferred to functional polymers with diverse structures and versatile properties because they are abundant, cheap, nontoxic, renewable, and sustainable. However, the polymerizations based on these green monomers are to be further developed. In this work, a facile CO_(2) and alkyne-based one-pot, two-step, fourcomponent tandem polymerization was successfully established. The polymerization of CO_(2), diynes, alkyl dihalides, and primary/secondary amines can proceed under mild reaction conditions and regio-and stereoregular poly(aminoacrylate)s with good solubility and thermal stability were obtained in high yields(up to 95%). Notably, distinctly different stereoregularity of resultant poly(aminoacrylate)s was realized via using primary or secondary amines. Using the former would readily generate polymers with 100% Z-isomers, whereas the latter furnished products with over 95% E-isomers. Through different monomer combination, the polymers with tunable structures and properties were ***, the tetraphenylethene units containing poly(aminoacrylate)s, showing the unique aggregation-induced emission characteristics,could function as a fluorescent probe for sensitive explosive detection. Thus, this work not only develops a facile CO_(2) and alkyne-based multicomponent tandem polymerization but also provides a valuable strategy to fine-tune the polymer structures and properties, which could be potentially applied in diverse areas.

关键词： Carbon dioxide Multicomponent tandem polymerization Aggregation-induced emission Green monomer

Study on 6-DOF active vibration-isolation system of the ultra-precision turning lathe based on GA-BP-PID control for dynamic loads

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Advances in Manufacturing 2024年第1期12卷 33-60页

作者： bo Wang zhong Jiang Pei-Da Hu Department of Precision Instrument Tsinghua UniversityBeijing100084People’s Republic of China Institute of Machinery Manufacturing Technology China Academy of Engineering PhysicsMianyang621900SichuanPeople’s Republic of China

The vibration disturbance from an external environment affects the machining accuracy of ultra-precision machining *** active vibration-isolation systems(AVIS)have been developed based on static *** a vibration-isolation load changes dynamically during ultra-precision turning lathe machining,the system parameters change,and the efficiency of the active vibration-isolation system based on the traditional control strategy *** solve this problem,this paper proposes a vibration-isolation control strategy based on a genetic algorithm-back propagation neural network-PID control(GA-BP-PID),which can automatically adjust the control parameters according to the machining ***-isolation simulations and experiments based on passive vibration isolation,a PID algorithm,and the GA-BP-PID algorithm under dynamic load machining conditions were *** experimental results demonstrated that the active vibration-isolation control strategy designed in this study could effectively attenuate vibration disturbances in the external environment under dynamic load *** design is reasonable and feasible.

关键词： Ultra-precision diamond turning lathe Active vibration isolation Six degrees of freedom Dynamic load Genetic algorithm-back propagation neural network-PID(GA-BP-PID)control

Experimental investigation of vortex generator influences on propeller cavitation and hull pressure fluctuations

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Journal of Hydrodynamics 2020年第1期32卷 82-92页

作者： Hong-bo Huang yun Long Bin Ji National Key Laboratory on Ship Vibration and Noise China Ship Scientific Research CenterWiuxi 214082China State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China

In this paper,the transient turbulent cavitating flow around a marine propeller behind a ship was investigated experimentally with emphasis on how vortex generator(VG)influences propeller cavitation and hull pressure *** experiments were carried out in China Large Cavitation Channel with the closed test section covering 10.5 m in length and cross-section of 2.2 m^2×2.0m^*** experiment recorded instantaneous cavitation photos of the propeller and pressure fluctuations on the hull *** results demonstrate that without vortex generator,the sheet cavitation inception begins at-50°(310°),and then from-50°(310°)to 30°,the extent and area of sheet cavitation *** vortex generator installed on the hull,the sheet cavitation inception occurs in advance at-60°(300°),and the sheet cavitation expands to larger rotation range due to the vortex *** is shown that the vortex generator with proper geometry and installed location may contribute the highly nonuniform wake to be more uniform,and can make the change of propeller cavitation to be milder,which decrease the pressure fluctuations in this *** analysis indicates that the vortex generator may promote the energy distribution to be more uniform in physical and spectral space in some degree.

关键词： Cavitating flow pressure fluctuations propeller and ship hull vortex generator

Formation Mechanism of Biomass Aromatic Hydrocarbon Tar on Quantum Chemistry

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Journal of Renewable Materials 2022年第12期10卷 3491-3504页

作者： bo Chen bo Liu Yong Chao Chao zhong School of Mechanical Engineering Hunan Institute of EngineeringXiangtan411104China School of Electrical and Information Engineering Hunan Institute of EngineeingXiangtan411104China Hunan Shuanghuan Fiber Forming Equipment Co ItdXiangtan411100China

The formation process of aromatic hydrocarbon tar during the pyrolysis process of biomass components of cel-lulose and lignin was carried out by quantum chemical calculation based on density functional theory method B3LYP/6-31G++(d,p).5 Hydroxymethylfurfural was chosen as the model compound of cellulose and hemicel-lulose,and syringa ldehyde was chosen as the model compound of *** calculation results show that the formation process of cellulose monocyclic aromatic hydrocarbon tar is the conversion process of benzene ring from furan ring,and the highest reaction energy barrier appears in the process of decarbonylation,which is 370.8 kJ/*** formation of lignin monocyclic aromatic hydrocarbon tar is mainly the process of side chains removal and the formation of phenol,The highest reaction energy barrier appears in the process of decarbonyla-tion,which is 374.9 kJ/*** reaction mechanism of phenanthrene formation from naphthalene was selected as the formation of cellulose and lignin polycydic aromatic hydrocarbon *** calculation results show that he total barrier of the pathway that naphthalene dehydrogenates to form naphthalene free radicals and then reacts with ethylene twice by addition action,finally occurs cydization reactions and isomerizes to produce phenan-threne is lowest,that is 38.6 kJ/*** it is proved that the evolution of tar is the process of deoxygenation and cyclization with the increase of the temperature from a theoretical point of view.

关键词： Cellulose lignin tar aromatic hydrocarbon quantum chemistry