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Chinese Journal of Aeronautics 2024年第2期37卷 482-500页

作者： xiaohe WANG Zengqiang CAO Yuehaoxuan WANG Yingjiang GUO School of Mechanical Engineering Northwestern Polytechnical UniversityXi’an 710072China NPU Xuhang Electromagnetic technology Co. Ltd.Xi’an 710100China

As the controlled research of Dynamic Installation(DI)and Static Installation(SI),a new interference installation method was developed based on electromagnetic loading to enhance the mechanical properties of composite structures.Four different interference-fit sizes were considered,ranging from a net fit to 2.0%.The experiments were conducted to evaluate the installation resistance and the mechanical behavior of the joint under external loads.Meanwhile,an FFA model to model the stress distribution and damage behavior of the bolt-hole contact interface was established.The load-displacement curve and damage modes of experiments were used to verify the FEA results.The results show that the installation resistance during DI process was remarkably lower than that of SI process corresponding to all interference-fit sizes,and the stress amplitudes induced by interference were larger and widely distributed.The damage of the hole wall was positively correlated with interference fit size,but DI can significantly reduce the damage compared to SI.In performance tests,DI enhanced the static bearing capacity and extended longer fatigue life of the joints than SI.DI methods can be an effective way to achieve highly reliable interference joints in composite structures.

关键词： Carbon Fiber-Reinforced Polymer(CFRP) Bolted joints Interference-fit Electromagnetic installation Finite Element Analysis(FEA) Damage mechanics Bearing behavior

Covalently Bonded Ni Sites in Black Phosphorene with Electron Redistribution for Efficient Metal‑Lightweighted Water Electrolysis

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Nano-Micro Letters 2024年第6期16卷 233-245页

作者： Wenfang Zhai Ya Chen Yaoda Liu Yuanyuan Ma Paranthaman Vijayakumar Yuanbin Qin Yongquan Qu Zhengfei Dai State Key Laboratory for Mechanical Behavior of Materials Xi’an Jiaotong UniversityXi’an 710049People’s Republic of China School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China SSN research Centre SSN College of EngineeringChennaiTamil Nadu 603110India

The metal-lightweighted electrocatalysts for water splitting are highly desired for sustainable and economic hydrogen energy deployments,but challengeable.In this work,a low-content Ni-functionalized approach triggers the high capability of black phosphorene(BP)with hydrogen and oxygen evolution reaction(HER/OER)bifunctionality.Through a facile in situ electro-exfoliation route,the ionized Ni sites are covalently functionalized in BP nanosheets with electron redistribution and controllable metal contents.It is found that the as-fabricated Ni-BP electrocatalysts can drive the water splitting with much enhanced HER and OER activities.In 1.0 M KOH electrolyte,the optimized 1.5 wt%Nifunctionalized BP nanosheets have readily achieved low overpotentials of 136 mV for HER and 230 mV for OER at 10 mA cm^(−2).Moreover,the covalently bonding between Ni and P has also strengthened the catalytic stability of the Ni-functionalized BP electrocatalyst,stably delivering the overall water splitting for 50 h at 20 mA cm^(−2).Theoretical calculations have revealed that Ni–P covalent binding can regulate the electronic structure and optimize the reaction energy barrier to improve the catalytic activity effectively.This work confirms that Ni-functionalized BP is a suitable candidate for electrocatalytic overall water splitting,and provides effective strategies for constructing metal-lightweighted economic electrocatalysts.

关键词： Black phosphorus Water electrolysis Electrocatalyst Electron redistribution Covalent functionalization

Neural networks-based iterative learning control consensus for periodically time-varying multi-agent systems

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Science China(Technological Sciences) 2024年第2期67卷 464-474页

作者： CHEN Jiaxi LI JunMin CHEN WeiSheng GAO WeiFeng School of Mathematics and Statistics Xidian UniversityXi'an 710071China School of Aerospace Science and technology Xidian UniversityXi'an 710071China

In this paper,the problem of adaptive iterative learning based consensus control for periodically time-varying multi-agent systems is studied,in which the dynamics of each follower are driven by nonlinearly parameterized terms with periodic disturbances.Neural networks and Fourier base expansions are introduced to describe the periodically time-varying dynamic terms.On this basis,an adaptive learning parameter with a positively convergent series term is constructed,and a distributed control protocol based on local signals between agents is designed to ensure accurate consensus of the closed-loop systems.Furthermore,consensus algorithm is generalized to solve the formation control problem.Finally,simulation experiments are implemented through MATLAB to demonstrate the effectiveness of the method used.

关键词： multi-agent systems adaptive iterative learning control nonlinearly parameterized dynamics Fourier series expansion neural networks

research on shell-side heat and mass transfer with multi-component in LNG spiral-wound heat exchanger under sloshing conditions

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Petroleum Science 2024年第2期21卷 1333-1345页

作者： Xue-Ping Du Guang-Lei Yu Ya-Cheng Xu Zhi-Jie Chen Nai-Liang Li Huan-Guang Wang School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina Key Laboratory of Thermo-Fluid Science and Engineering MOEXi©an Jiaotong UniversityXi'an710049ShaanxiChina xi©an Aerospace Propulsion Test technology Institute Xi©an710100ShaanxiChina

The spiral-wound heat exchanger(SWHE) is the primary low-temperature heat exchanger for large-scale LNG plants due to its high-pressure resistance, compact structure, and high heat exchange efficiency. This paper studied the shell-side heat and mass transfer characteristics of vapor-liquid two-phase mixed refrigerants in an SWHE by combining a multi-component model in FLUENT software with a customized multicomponent mass transfer model. Besides, the mathematical model under the sloshing condition was obtained through mathematical derivation, and the corresponding UDF code was loaded into FLUENT as the momentum source term. The results under the sloshing conditions were compared with the relevant parameters under the steady-state condition. The shell-side heat and mass transfer characteristics of the SWHE were investigated by adjusting the component ratio and other working conditions. It was found that the sloshing conditions enhance the heat transfer performance and sometimes have insignificant effects. The sloshing condition is beneficial to reduce the flow resistance. The comprehensive performance of multi-component refrigerants has been improved and the improvement is more significant under sloshing conditions, considering both the heat transfer and pressure drop.These results will provide theoretical support for the research and design of multi-component heat and mass transfer enhancement of LNG SWHE under ocean sloshing conditions.

关键词： Spiral-wound heat exchanger Sloshing conditions Two-phase flow Multi-component Heat and mass transfer

A polarization sensitive interferometer:Delta interferometer

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Chinese Physics B 2024年第3期33卷 369-377页

作者：卫超奇刘建彬董翼飞孙雨农周宇郑淮斌刘严严闫秀生李福利徐卓 Key Laboratory of Multifunctional Materials and Structures Ministry of Education & International Center for Dielectric ResearchSchool of Electronic Science and EngineeringXi'an Jiaotong UniversityXi'an 710049China MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Department of Applied PhysicsXi'an Jiaotong UniversityXi'an 710049China Science and technology on Electro-Optical Information Security Control Laboratory Tianjin 300308China

A new type of polarization sensitive interferometer is proposed,named the Delta interferometer,inspired by its geometry resembling the Greek letter Delta.The main difference between the Delta interferometer and other existing interferometers,such as Michelson,Mach-Zehnder and Young's double-slit interferometers,is that the two interfering paths are asymmetrical in the Delta interferometer.The visibility of the first-order interference pattern observed in the Delta interferometer is dependent on the polarization of the incidental light.Optical coherence theory is employed to interpret this phenomenon and single-mode continuous-wave laser light is employed to verify the theoretical predictions.The theoretical and experimental results are consistent.The Delta interferometer is a perfect tool to study the reflection of electromagnetic fields in different polarizations and may find applications in polarization-sensitive scenarios.

关键词： phase sensitive interferometer Fresnel formula first-order interference

DIR:Dynamic Request Interleaving for Improving the Read Performance of Aged Solid-State Drives

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Journal of Computer Science & technology 2024年第1期39卷 82-98页

作者：聂世强张驰伍卫国 Department of Computer Science and technology Xi'an Jiaotong UniversityShaanci 710049China

Triple-level cell(TLC)NAND flash is increasingly adopted to build solid-state drives(SSDs)for modern computer systems.While TLC NAND flash effectively improves storage density,it faces severe reliability issues;in partic-ular,the pages exhibit different raw bit error rates(RBERs).Integrating strong low-density parity-check(LDPC)code helps to improve reliability but suffers from prolonged and proportional read latency due to multiple read retries for worse pages.The straightforward idea is that dispersing page-size data across several pages in different types can achieve a low-er average RBER and reduce the read latency.However,directly implementing this simple idea into flash translation lay-er(FTL)induces the read amplification issue as one logic page residing in more than one physical page brings several read operations.In this paper,we propose the Dynamic Request Interleaving(DIR)technology for improving the performance of TLC NAND flash-based SSDs,in particular,the aged ones with large RBERs.DIR exploits the observation that the la-tency of an I/O request is determined,without considering the queuing time,by the access of the slowest device page,i.e.,the page that has the highest RBER.By grouping consecutive logical pages that have high locality and interleaving their encoded data in different types of device pages that have different RBERs,DIR effectively reduces the number of read re-tries for LDPC with limited read amplification.To meet the requirement of allocating hybrid page types for interleaved data,we also design a page-interleaving friendly page allocation scheme,which splits all the planes into multi-plane re-gions for storing the interleaved data and single-plane regions for storing the normal data.The pages in the multi-plane re-gion can be read/written in parallel by the proposed multi-plane command and avoid the read amplification issue.Based on the DIR scheme and the proposed page allocation scheme,we build DIR-enable FTL,which integrates the proposed schemes into the FTL with some modificatio

关键词： triple-layer cell solid-state drive(TLC SSD) performance interleaving data unbalanced bit error rate

Role of 5-hydroxytryptamine type 3 receptors in the regulation of anxiety reactions

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第1期25卷 23-37页

作者： Yinan DU Zhiwei LI Yukui ZHAO Jing HAN Weiping HU Zhiqiang LIU MOE Key Laboratory of Modern Teaching technology Shaanxi Normal UniversityXi’an710062China

5-Hydroxytryptamine(5-HT)type 3 receptor(5-HT_(3)R)is the only type of ligand-gated ion channel in the 5-HT receptor family.Through the high permeability of Na+,K+,and Ca2+and activation of subsequent voltage-gated calcium channels(VGCCs),5-HT_(3)R induces a rapid increase of neuronal excitability or the release of neurotransmitters from axon terminals in the central nervous system(CNS).5-HT_(3)Rs are widely expressed in the medial prefrontal cortex(mPFC),amygdala(AMYG),hippocampus(HIP),periaqueductal gray(PAG),and other brain regions closely associated with anxiety reactions.They have a bidirectional regulatory effect on anxiety reactions by acting on different types of cells in different brain regions.5-HT_(3)Rs mediate the activation of the cholecystokinin(CCK)system in the AMYG,and theγ-aminobutyric acid(GABA)“disinhibition”mechanism in the prelimbic area of the mPFC promotes anxiety by the activation of GABAergic intermediate inhibitory neurons(IINs).In contrast,a 5-HT_(3)R-induced GABA“disinhibition”mechanism in the infralimbic area of the mPFC and the ventral HIP produces anxiolytic effects.5-HT_(2)R-mediated regulation of anxiety reactions are also activated by 5-HT_(3)R-activated 5-HT release in the HIP and PAG.This provides a theoretical basis for the treatment of anxiety disorders or the production of anxiolytic drugs by targeting 5-HT_(3)Rs.However,given the circuit specific modulation of 5-HT_(3)Rs on emotion,systemic use of 5-HT_(3)R agonism or antagonism alone seems unlikely to remedy anxiety,which deeply hinders the current clinical application of 5-HT_(3)R drugs.Therefore,the exploitation of circuit targeting methods or a combined drug strategy might be a useful developmental approach in the future.

关键词： 5-Hydroxytryptamine type 3 receptor(5-HT_(3)R) Anxiety Medial prefrontal cortex Amygdala Hippocampus Periaqueductal gray

Regulating the conductance of tungsten diselenide by oxygen plasma and improving its electrical stability by encapsulation

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Nano research 2024年第4期17卷 3253-3260页

作者： Zhaofang Cheng Shaodan He Shimin Zhang Shijun Duan Min Wang Ziyu Liu Rong Zhang Wenya Qiang Xudong Zhang Minggang xia MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Department of Applied Physics School of PhysicsXi’an Jiaotong UniversityXi’an 710049China Shaanxi Province Key Laboratory of Quantum Information and Optoelectronic Quantum Devices School of PhysicsXi’an Jiaotong UniversityXi’an 710049China

Two-dimensional(2D)tungsten selenide(WSe_(2))is promising candidate material for future electronic applications,owing to its potential for ultimate device scaling.For improving the electronic performance of WSe_(2)-based field-effect transistors(FETs),the modification of surface properties is essential.In this study,the seamless structural phase transition in WSe_(2) lattice is achieved by soft oxygen plasma,regulating the electrical conductance of WSe_(2)-based FETs.We found that during the soft oxygen plasma treatment with optimal processing time,the generated oxygen ions can substitute some selenium atoms and thus locally modify the bond length,inducing 2H→1T phase transition in WSe_(2) with seamless interfaces.The mosaic structures have been proven to tailor the electronic structure and increase the hole carrier concentration inside WSe_(2),significantly increasing the channel conductance of WSe_(2) FETs.With the further increase of the oxygen plasma treatment time,the creation of more selenium vacancy defects leads to the electronic doping,resulting in the reduction of conductance.Benefiting from the hexagonal boron nitride(h-BN)encapsulation to interrupt the partial structural relaxation from 1T to 2H phase,our WSe_(2) FET exhibits high electronic stability with conductance of 6.8×10^(-4) S,which is about four orders of magnitude higher than 2H WSe_(2)(5.8×10^(-8) S).This study could further broaden the WSe_(2) FETs in applications for functionalization and integration in electronics.

关键词： tungsten selenide(WSe2) structural phase transition oxygen plasma conductance hexagonal boron nitride(h-BN)encapsulation

Remodeling the tumor microenvironment by vascular normalization and GSH-depletion for augmenting tumor immunotherapy

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Chinese Chemical Letters 2024年第2期35卷 329-334页

作者： Jin Wang Qingqing Zhang Yanchen Li xiaoyan Pan Yuanyuan Shan Jie Zhang School of Pharmacy Health Science CenterXi'an Jiaotong UniversityXi'an 710061China Department of Pharmacy The First Affiliated Hospital of Xi'an Jiaotong UniversityXi'an 710061China

Remodeling tumor microenvironment(TME)is a very promising and effective strategy to enhance the effects of chemotherapy,photodynamic therapy,and immunotherapy.Normalization of tumor vasculature as well as depletion of glutathione(GSH)can improve the TME.Here,we developed a novel therapeutic nanoparticle functional enzyme ultra QDAU5 nanoparticles(FEUQ Nps)based on a fluorescence-on and releasable strategy by combining a vascular normalization inducer,a GSH depleting agent,and an activated fluorophore.In which the cleavage of disulfide bonds releases active molecules that induce vascular normalization and improve the hypoxic microenvironment.In addition,it may deplete GSH in cancer cells,thus inducing the production of reactive oxygen species(ROS)and lipid peroxide(LPO)and promoting iron toxicity.It may also lead to endoplasmic stress and release of calmodulin,which activates the immune system.Meanwhile,quenched fluorophores are turned on in the presence of galactosidase(GLU)for tumor-specific labeling.In summary,we developed novel therapeutic agent nanoparticles with the function of vascular normalization inducers to achieve specific labeling of hepatocellular carcinoma while exerting efficient antitumor effects in vivo.

关键词： Vascular normalization Tumor microenvironment GSH depletion Ferroptosis Activated immune

Demand and key technology for a LEO constellation as augmentation of satellite navigation systems

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Satellite Navigation 2024年第1期5卷 1-9页

作者： Yuanxi Yang Yue Mao xia Ren xiaolin Jia Bjiao Sun xi’an research Institute of Surveying and Mapping Xi’an710054ShaanxiChina State National Key Laboratory of Geo-Information Engineering Xi’an710054ShaanxiChina

A Low Earth Orbit(LEO)constellation augmenting satellite navigation is important in the future development of Global Navigation Satellite System(GNSS).GNSS augmented by LEO constellations can improve not only the accuracy of Positioning,Navigation,and Timing(PNT),but also the consistency and reliability of secure PNT system.This paper mainly analyzes the diverse demands of different PNT users for LEO augmented GNSS,including the precision demand in real-time,the availability demand in special areas,the navigation signal enhancement demand in complex electromagnetic environments,and the integrity demand with high security.Correspondingly,the possible contributions of LEO constellations to PNT performance are analyzed from multiple aspects.A particular attention is paid to the special PNT user requirements that cannot be fulfilled with existing GNSS,such as the PNT service demand in the polar regions and the onboard GNSS orbit determination demand of some LEO satellites.The key technologies to be considered in the constellation design,function realization,and payload development of the LEO-augmented navigation system are summarized.

关键词： Low earth orbit navigation constellation Accuracy augmentation Orbit determination Integrity