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Chinese Journal of Aeronautics 2024年第2期37卷 524-540页

作者： Xuan CUI rui zhao Min WAn School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

Electrically Assisted Forming(EAF)technology has obvious advantages in material *** develop an effective constitutive model considering electrical effects,room temperature and electrically assisted quasi-static uniaxial tensile tests were conducted using ultrathin nickelbased superalloy plates with a thickness of 0.25 *** research focused on the two most widely recognized effects:the Joule thermal and the electric athermal *** mechanism of current action can be divided into two scenarios:one considering the Joule thermal effect only,and the other considering both effects *** basic constitutive models,namely the Modified-Hollomon model and the Johnson-Cook(J-C)model,were selected to be optimized through the classification of two different situations,and four optimized constitutive models were *** was found that the J-C model with simultaneous consideration of the Joule thermal effect and electric athermal effect had the best prediction effect by comparing the results of these four ***,the accuracy of the optimization model was verified by finite element simulation of the electrically assisted stretching optimization *** results show that the constitutive model can effectively predict the temperature effect caused by the Joule heat effect and the athermal effect of current on the material.

关键词： Joule heating Elastoplasticity Plastic deformation Superalloys Constitutive models

Plasma-exfoliated g-C_(3)n_(4) with oxygen doping: tailoring photocatalytic properties

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Frontiers of Chemical Science and Engineering 2024年第2期18卷 27-39页

作者： Yuxin li Junxin Guo rui Han zhao Wang national Engineering Research Centre of Industry Crystallization Technology School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China

Heteroatom doping and defect engineering have been proposed as effective ways to modulate the energy band structure and improve the photocatalytic activity of g-C_(3)n_(4). In this work, ultrathin defective g-C_(3)n_(4) was successfully prepared using cold plasma. Plasma exfoliation reduces the thickness of g-C_(3)n_(4) from 10 nm to 3 nm, while simultaneously introducing a large number of nitrogen defects and oxygen atoms into g-C_(3)n_(4). The amount of doped O was regulated by varying the time and power of the plasma treatment. Due to n vacancies, O atoms formed strong bonds with C atoms, resulting in O doping in g-C_(3)n_(4). The mechanism of plasma treatment involves oxygen etching and gas expansion. Photocatalytic experiments demonstrated that appropriate amount of O doping improved the photocatalytic degradation of rhodamine B compared with pure g-C_(3)n_(4). The introduction of O optimized the energy band structure and photoelectric properties of g-C_(3)n_(4). Active species trapping experiments revealed ·O_(2)^(–) as the main active species during the degradation.

关键词： graphitic carbon nitride cold plasma oxygen doping nitrogen defect visible-light photocatalysis

Microstructure evolution and mechanical properties of brazing joint for ultra-thin-walled Inconel 718 considering grain size effect and brazing temperature

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Chinese Journal of Aeronautics 2024年第2期37卷 541-556页

作者： rui zhao Yueshuai SOnG Hui KAnG Min WAn School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Jiangxi Research Institute of Beihang University Jiangxi 330000China

The systematic investigation of the mechanical properties and microstructure evolution process of ultra-thin-walled Inconel 718 capillary brazing joints is of great significance because of the exceptionally high demands on its *** achieve this objective,this study investigates the impact of three distinct brazing temperatures and five typical grain sizes on the brazed joints’mechanical properties and microstructure evolution *** evolution analysis was conducted based on Electron Back Scatter Diffraction(EBSD),Scanning Electron Microscopy(SEM),X-Ray Diffraction(XRD),High-Resolution Transmission Electron Microscopy(HRTEM),and Focused Ion Beam(FIB).Besides,the mechanical properties and fracture behavior were studied based on the uniaxial tension tests and in-situ tension *** findings reveal that the brazing joint’s strength is higher for the fine-grain capillary than the coarse-grain one,primarily due to the formation of a dense branch structure composed of G-phase in the brazing *** effects of grain size,such as pinning and splitting,are amplified at higher brazing ***,micro-cracks initiate around brittle intermetallic compounds and propagate through the eutectic zone,leading to a cleavage fracture *** fracture stress of fine-grain specimens is higher than that of coarse-grain due to the complex micro-crack ***,this study contributes significantly to the literature by highlighting the crucial impact of grain size on the brazing properties of ultra-thin-walled Inconel 718 structures.

关键词： EYWORDS Ultra-thin-walled structure Brazing Inconel 718 Grain size effect Brazing temperature

The Multi-parameter Test of Gravitational Wave Dispersion with Principal Component Analysis

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Research in Astronomy and Astrophysics 2024年第5期24卷 140-150页

作者： Zhi-Chu Ma rui niu Wen zhao CAS Key laboratory for Research in Galaxies and Cosmology Department of AstronomyUniversity of Science and Technology of ChinaHefei 230026China School of Astronomy and Space Sciences University of Science and Technology of ChinaHefei 230026China

In this work, we consider a conventional test of gravitational wave(GW) propagation which is based on the phenomenological parameterized dispersion relation to describe potential departures from General Relativity(GR)al.ng the propagation of GWs. But different from tests conventionally performed previously, we vary multiple deformation coefficients simultaneously and employ the principal component analysis(PCA) method to remedy the strong degeneracy among deformation coefficients and obtain informative posteriors. The dominant PCA components can be better measured and constrained, and thus are expected to be more sensitive to potential departures from the waveform model. Using this method we analyze ten selected events and get the result that the combined posteriors of the dominant PCA parameters are consistent with GR within 99.7% credible intervals. The standard deviation of the first dominant PCA parameter is three times smaller than that of the original dispersion parameter of the leading order. However, the multi-parameter test with PCA is more sensitive to not only potential deviations from GR but also systematic errors of waveform models. The difference in results obtained by using different waveform templates hints that the demands of waveform accuracy are higher to perform the multiparameter test with PCA. Whereas, it cannot be strictly proven that the deviation is indeed and only induced by systematic errors. It requires more thorough research in the future to exclude other possible reasons in parameter estimation and data processing.

关键词： gravitational waves-gravitation-black hole physics

Molecular mechanism of flowering time regulation in Brassica rapa:similarities and differences with Arabidopsis

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Horticultural Pl.nt Journal 2024年第3期10卷 615-628页

作者： na li rui Yang Shuxing Shen Jianjun zhao State Key laboratory of north China Crop Improvement and Regulation Key Laboratory of Vegetable Germplasm Innovation and Utilization of HebeiCollaborative Innovation Center of Vegetable Industry in HebeiCollege of HorticultureHebei Agricultural UniversityBaodingHebei 071000China

Properly regulated flowering time is pivotal for successful pl.nt *** floral transition from vegetative growth to reproductive growth is regulated by a complex gene regulatory network that integrates environmental signals and internal conditions to ensure that flowering takes place under favorable *** rapa is a diploid Cruciferae species that includes several varieties that are cultivated as vegetable or oil *** time is one of the most important agricultural traits of *** crops because of its influence on yield and *** transition to flowering in *** is regulated by several environmental and developmental cues,which are perceived by several signal.ng pathways,including the vernalization pathway,the autonomous pathway,the circadian clock,the thermosensory pathway,and gibberell.n(GA)*** signals are integrated to control the expression of floral integrators BrFTs and BrSOC1s to regulate *** this review,we summarized current research advances on the molecular mechanisms that govern flowering time regulation in *** and compare this to what is known in Arabidopsis.

关键词： Flowering time Brassica rapa Vernalization Photoperiod

Electrothermal Model Based Remaining Charging Time Prediction of lithium-Ion Batteries against Wide Temperature Range

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Chinese Journal of Mechanical Engineering 2024年第2期37卷 330-339页

作者： rui Xiong Zian zhao Cheng Chen Xinggang li Weixiang Shen School of Mechanical Engineering Beijing Institute of TechnologyBeijing 100081China School of Science Computing and Engineering TechnologiesSwinburne University of TechnologyHawthornVIC 3122Australia

Battery remaining charging time(RCT)prediction can facilitate charging management and alleviate mileage anxiety for electric vehicles(EVs).Also,it is of great significance to improve EV users’***,the RCT for a lithiumion battery pack in EVs changes with temperature and other battery *** study proposes an electrothermal model-based method to accurately predict battery ***,a characteristic battery cell is adopted to represent the battery pack,thus an equival.nt circuit model(ECM)of the characteristic battery cell is established to describe the electrical behaviors of a battery ***,an equival.nt thermal model(ETM)of the battery pack is developed by considering the influence of ambient temperature,thermal management,and battery connectors in the battery pack to calculate the temperature which is then fed back to the ECM to realize electrothermal ***,the RCT prediction method is proposed based on the electrothermal model and validated in the wide temperature range from-20℃to 45℃.The experimental results show that the prediction error of the RCT in the whole temperature range is less than 1.5%.

关键词： Electric vehicles lithium-ion batteries Remaining charging time Electrothermal model

Examination of two-phase behaviors in porous media during pool boil.ng

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Science China(Technological Sciences) 2024年第6期67卷 1695-1713页

作者： ZHAnG ZhiHao GUAn ShuYa WU rui zhao ChangYing School of Mechanical Engineering Shanghai Jiao Tong University

The enhancement of pool boil.ng heat transfer using porous media has been extensively *** the two-phase distribution and evolution in porous media are crucial to the heat transfer performance,including the critical heat flux(CHF)and heat transfer coefficient(HTC),direct observation of the two-phase flow inside the media is limited owing to the blockage of the direct view from the porous *** this study,pool boil.ng visualization experiments were conducted on porous samples with different throat widths in deionized *** results showed that the HTC increased with the throat ***,the growth-contraction cycle of the vapor region and the formation and drying of the wall liquid film inside the porous media were *** vapor region,including the maximum and minimum areas in the boil.ng cycle,was quantitatively ***,the relationship between the minimum gas-phase area and HTC peak was identified.A one-dimensional transient model was developed considering solid skeleton heat conduction,liquid film evaporation,and vapor region growth to quantitatively study the influence of heat flux on the internal two-phase *** model successfully captured the maximum gas-phase area,duration of boil.ng cycles,and HTC trends at specific heat *** results of this quantitative study provide insights into the internal two-phase distribution and evolution induced by pool boil.ng.

关键词： porous media two-phase behaviors pool boil.ng

Effect of l.ng reaction distance on gas composition from organic-rich shale pyrolysis under high-temperature steam environment

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International Journal of Coal Science & Technology 2024年第3期11卷 102-119页

作者： lei Wang rui Zhang Guoying Wang Jing zhao Dong Yang Zhiqin Kang Yangsheng zhao Key laboratory of In-Situ Property Improving Mining of Ministry of Education Taiyuan University of TechnologyTaiyuan030024China The In-Situ Steam Injection Branch of State Center for Research and Development of Organic-Rich Shale Exploitation Taiyuan University of TechnologyTaiyuan030024China College of Mining Engineering Taiyuan University of TechnologyTaiyuan030024China School of Energy Science and Engineering Henan Polytechnic UniversityJiaozuo454002China

When high-temperature steam is used as a medium to pyrolyze organic-rich shale,water steam not only acts as heat transfer but also participates in the chemical reaction of organic matter pyrolysis,thus affecting the generation law and release characteristics of gas *** this study,based on a l.ng-distance reaction system of organic-rich shale pyrolysis via steam injection,the effects of steam temperature and reaction distance on gas product composition are analyzed in depth and compared with other pyrolysis *** advantages of organic-rich shale pyrolysis via steam injection are then *** volume concentration of hydrogen in the gas product obtained via the steam injection pyrolysis of organic-rich shale is the highest,which is more than 60%.The hydrogen content increases as the reaction distance is extended;however,the rate of increase changes *** the reaction distance from 800 to 4000 mm increases the hydrogen content from 34.91%to 69.68%and from 63.13%to 78.61%when the steam temperature is 500°C and 555°C,***,the higher the heat injection temperature,the smaller the reaction distance required to form a high concentration hydrogen pyrolysis environment(hydrogen concentration>60%).When the steam pyrolysis temperature is increased from 500°C to 555°C,the reaction distance required to form a high concentration of hydrogen is reduced from 3800 to 800 *** with the direct retorting process,the volume concentration of hydrogen obtained from high-temperature steam pyrolysis of organic-rich shale is 8.82 and 10.72 times that of the commonly used Fushun and Kivite furnaces,*** pyrolysis of organic-rich shale via steam injection is a pyrolysis process in a hydrogen-rich environment.

关键词： Steam temperature Pyrolysis gas Hydrogen-rich Reaction distance Direct retorting

Authenticated Digital Currency Redaction with Stronger Privacy and Usability

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China Communications 2024年第6期21卷 219-236页

作者： Tang Yongli li Ying zhao Zongqu li Yuanhong Guo rui School of Computer Science and Technology Henan Polytechnic UniversityJiaozuo 454000China School of Cyberspace Security Xi’an University of Posts and TelecommunicationsXi’an 710121China

With the promotion of digital currency,how to effectively solve the authenticity,privacy and usability of digital currency issuance has been a key *** signature scheme(RSS)can provide the verification of the integrity and source of the generated sub-documents and solve the privacy problem in digital currency by removing blocks from the signed ***,it has not realized the consolidation of signed documents,which can not solve the problem of merging two digital ***,we introduce the concept of weight based on the threshold secret sharing scheme(TSSS)and present a redactable signature scheme with merge algorithm(RSS-MA)using the quasi-commutative *** scheme can reduce the communication overhead by utilizing the merge algorithm when transmitting multiple digital currency ***,this can effectively hide the scale of users’private monetary assets and the number of transactions between *** meeting the three properties of digital currency issuance,in order to ensure the availability of digital currency after redacting,editors shall.not remove the relevant identification information block form digital ***,our security proof and the analysis of efficiency show that RSS-MA greatly improves the communication and computation efficiency when transmitting multiple signatures.

关键词： authenticity verification digital currency privacy protection RSS-MA TSSS usability

Building mm Wave on the Evolving C-V2X:mm Wave nR-V2X

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China Communications 2024年第1期21卷 88-101页

作者： Shanzhi Chen Xinxin He rui zhao Jinl.ng Hu Xin Zhang China Information and Communication Technology Group Co. Ltd.(CICT)the State Key Laboratory of Wireless Mobile CommunicationsBeijing 100083China Beijing laboratory of Advanced Information networks Beijing Key Laboratory of Network System Architecture and ConvergenceBeijing University of Posts and TelecommunicationsBeijing 100876China CICT Connected and Intelligent Technologies Co. LtdChina Academy of Telecommunication TechnologyBeijing 100191China CICT Mobile Communications Technology Co.ltd.

Since the evolving standardization of cellular V2X(C-V2X)technologies is continuously developed by 3GPP,research on new radio(nR-V2X)has been on schedule by academic and *** millimeter wave(mm Wave)frequency band is supposed to provide large transmission bandwidth,yet the development of mm Wave band in nR-V2X is still in preliminary *** this article,a comprehensive discussion of mm Wave nR-V2X is given covering trends,standardization l.ndscape,and enabl.ng technologies,aiming at tackl.ng the chall.nge of channel model.ng,directional channel access,beamforming and blockage *** vision of mm Wave nR-V2X is to fully support the development of automated driving,holographic control display and improved in-car infotainment for the future.

关键词： C-V2X enabl.ng technologies mmWave nR-V2X