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Journal of Hydrodynamics 2024年第1期36卷 184-201页

作者： Xiao-qi Jia shuai-kang Zhang Zu-chao Zhu Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou310018China

To reveal the cavitation forms of tip leakage vortex(TLV)of the axial flow pump and the flow mechanism of the flow field,this research adopts the partially-averaged Navier-Stokes(PANS)model to simulate the cavitation values of an axial flow pump,followed by experimental *** experimental result shows that compared with the shear stress transport(SST)k-ωmodel,the PANS model significantly reduces the eddy viscosity of the flow field to make the vortex structure clearer and allow the turbulence scale to be more robustly *** cavitation area within the axial flow pump mainly comprises of TLV cavitation,clearance cavitation and tip leakage flows combined effect of triangular cloud cavitation *** formation and development of cavitation are accompanied by the formation and evolution of vortex,and variations in vortex structure also generate and promote the development of *** addition,an in-depth analysis of the relationship between the turbulent kinetic energy(TKE)transport equation and cavitation patterns was also conducted,finding that the regions with relatively high TKE are mainly distributed around gas/liquid boundaries with serious cavitation and evident gas-liquid *** phenomenon is mainly attributed to the combined effect of the pressure action term,stress diffusion term and TKE production term.

关键词： Cavitation axial flow pump tip leakage vortex(TLV) partially-averaged Navier-Stokes(PANS)model turbulent kinetic energy(TKE)

Unlocking high-efficiency oxygen evolution reaction through Co-N coordination engineering in Co@N-doped porous carbon core–shell nanoparticles

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Nano Research 2024年第8期17卷 7068-7076页

作者： Shucheng Liu Yu shuai Xiaosi qi Zhao Ding Yi Liu College of Big Data and Information Engineering Guizhou UniversityGuiyang 550025China College of Physics Guizhou Province Key Laboratory for Photoelectrics Technology and ApplicationGuizhou UniversityGuiyang 550025China

Modulation of metal sites coordination can significantly refine the electronic architecture of catalysts,thereby improving their catalytic *** work successfully developed a core–shell Co@N-doped porous carbon(Co@NC)catalyst by pyrolyzing the COF/MOF(IISERP-COF3/ZIF-67)composite in an inert *** Co@NC catalyst exhibited impressive oxygen evolution reaction(OER)performance,with a small overpotential of 304 mV and a modest Tafel slope of 88.6 mV·dec^(−1)in a 1 M KOH,alongside remarkable stability,maintaining 98.5%of its activity over 13 *** role of IISERP-COF3 was pivotal in preventing Co atom aggregation during the ZIF-67 pyrolysis,which facilitated the creation of mesopores for enhanced mass transport and ***,it effectively modulated the Co-N coordination to fine-tune the electronic structure,thereby optimizing the catalyst's capacity for adsorption of intermediates and boosting its intrinsic *** functional theory(DFT)studies corroborate that the exceptional OER efficiency of Co@NC can be linked to the enhanced Co-N coordination,optimizing the localized electronic structure at the Co active *** study not only proposes an innovative approach for optimizing COF/MOF as effective electrocatalysts but also clears the path for the emergence of affordable,high-performance alternatives to precious metal-based catalysts,marking a significant advancement in sustainable energy technologies.

关键词： covalent organic framework(COF) metal-organic framework(MOF) core-shell structure catalysts oxygen evolution reaction

Design and calibration of spoke piezoelectric six-dimensional force/torque sensor for space manipulator

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Chinese Journal of Aeronautics 2024年第1期37卷 218-235页

作者： Yingjun LI Guicong WANG shuai ZHANG Yuanqin ZHOU Hongyu LI Zhenguang qi School of Mechanical Engineering University of JinanJinan 250022China

The large manipulator outside the space cabin is a multi-degree of freedom actuator for space *** order to realize the automatic control and flexible operation of the space manipulator,a novel spoke structure piezoelectric six-dimensional force/torque sensor with redundancy ability,high stiffness and good decoupling performance is innovatively *** on the deformation coordination relationship,the redundancy measurement mechanism is *** mathematical models of the sensor with and without branch fault are established *** finite element model is established to verify the feasibility of structure and redundancy measuring principle of the *** on the theoretical analysis and simulation analysis,the prototype of the sensor is *** and dynamic calibration experiments are carried *** actual output voltage signal of the six-dimensional force/torque sensor is collected to establish the equation between the standard input applied load and the actual output voltage *** on ant colony optimized BP algorithm,performance indexes of the sensor with and without branch fault are analyzed *** experimental results show that the spoke piezoelectric sixdimensional force/torque sensor with the eight-point support structure has good accuracy and ***,it has strong decoupling characteristic that can effectively shield the coupling between *** nonlinear errors and maximum interference errors of decoupled data with and without branch faults are less than 1% and 2%,*** natural frequency of the sixdimensional force sensor can reach 2856.45 Hz and has good dynamic *** research content lays a theoretical and experimental foundation for the design,development and application of the new six-dimensional force/torque sensors with ***,it will significantly improve the research level in this field,and provide a strong guarantee for the smoot

关键词： Decoupling algorithm Piezoelectric Redundancy Six-dimensional force/torque sensor Space manipulator

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Dual-assisted high-precision tracking technique for wideband multiplexed signals in new generation GNSS

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Satellite Navigation 2024年第1期5卷 52-73页

作者： Yunhan qi Zheng Yao Mingquan lu Department of Electronic Engineering Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology Beijing100084China

With the evolution of Global Navigation Satellite System(GNSS),new generation GNSS signals have adopted the dual-frequency multiplexing modulation techniques,which jointly modulate multiple signals located on multiple sub-frequencies into a Wideband Multiplexed Signal(WMS).Although WMSs were proposed initially to reduce the complexity of satellite transmitters and improve the transmission efficiency of signals,their multi-component structures and wide root mean square bandwidths introduced by high-frequency subcarriers also provide the possibility to improve the GNSS ranging ***,this paper proposes a Dual-assisted Multi-component Tracking(DMT)technique,which can not only fully use high-frequency subcarriers in WMSs,but also effectively track carrier,subcarrier,and code by jointly utilizing all components in *** this paper,the tracking and ranging performances of DMT are comprehensively analyzed theoretically and by simulation and real *** results show that compared with existing WMS tracking methods,DMT can achieve tracking results with lower tracking jitters and ranging results with higher precision,providing a highly advantageous solution for new generation GNSS signal processing.

关键词： Wideband multiplexed signal Dual-assisted Multi-component High precision tracking

Ionic liquid-based in situ dynamically self-assembled cationic lipid nanocomplexes(CLNs)for enhanced intranasal siRNA delivery

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Chinese Chemical Letters 2024年第7期35卷 367-371页

作者： luyu Zhang Zirong Dong shuai Yu Guangyue Li Weiwen Kong Wenjuan Liu Haisheng He Yi lu Wei Wu Jianping qi Key Laboratory of Smart Drug Delivery of MOE School of PharmacyFudan UniversityShanghai 201203China School of Pharmacy Shandong Academy of SciencesQilu University of TechnologyJi'nan 250353China College of Chemical Engineering North China University of Science and TechnologyTangshan 063210China

This research aims to develop a non-invasive strategy for small interfering RNA(siRNA)nasal delivery based on ionic liquids(ILs)and cationic lipid(2,3-dioleoyloxy-propyl)-trimethylammonium-chloride(DOTAP).Other than the classical role of penetration enhancer,ILs also acted as superior solvents to simultaneously load siRNA and DOTAP,forming siRNA-DOTAP-ILs(siRNA-DILs)*** nasal mucosa penetration,DOTAP and ILs components self-assembled into cationic lipid nanocomplexes to load siRNA for enhanced in situ *** siRNA-DILs demonstrated resistance against RNase,significant mucosa penetration,prolonged nasal retention,and satisfying gene-silencing efficacy at lower ***,DILs were also able to deliver KCa3.1-targeted siRNA effectively for the treatment of allergic rhinitis in rat model by nasal ***,DILs have great potentials to deliver biological macromolecules across nasal mucosa by in situ dynamic self-assembly.

关键词： Ionic liquids Cationic lipids Lipid nanoparticles siRNA Allergic rhinitis

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Neuronal conversion from glia to replenish the lost neurons

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Neural Regeneration Research 2024年第7期19卷 1446-1453页

作者： Shiyu Liang Jing Zhou Xiaolin Yu shuai lu Ruitian Liu National Key Laboratory of Biochemical Engineering Institute of Process EngineeringChinese Academy of SciencesBeijingChina School of Chemical Engineering University of Chinese Academy of SciencesBeijingChina Department of Geriatric Rehabilitation Beijing Rehabilitation HospitalCapital Medical UniversityBeijingChina

Neuronal injury,aging,and cerebrovascular and neurodegenerative diseases such as cerebral infarction,Alzheimer’s disease,Parkinson’s disease,frontotemporal dementia,amyotrophic lateral sclerosis,and Huntington’s disease are characte rized by significant neuronal *** rtunately,the neurons of most mammals including humans do not possess the ability to *** of lost neurons becomes an appealing therapeutic strategy to reve rse the disease *** of pluripotent neural stem cells can supplement the missing neurons in the brain,but it carries the risk of causing gene mutation,tumorigenesis,severe inflammation,and obstructive hydrocephalus induced by brain *** of neural or non-neural lineage cells into functional neurons is a promising strategy for the diseases involving neuron loss,which may overcome the above-mentioned disadvantages of neural stem cell *** far,many strategies to transfo rm astrocytes,fibroblasts,microglia,Muller glia,NG2 cells,and other glial cells to mature and functional neurons,or for the conversion between neuronal subtypes have been developed thro ugh the regulation of transcription factors,polypyrimidine tra ct binding protein 1(PTBP1),and small chemical molecules or are based on a combination of several factors and the location in the central nervous ***,some recent papers did not obtain expected results,and discrepancies ***,in this review,we discuss the history of neuronal transdifferentiation,summarize the strategies for neuronal replenishment and conversion from glia,especially astrocytes,and point out that biosafety,new strategies,and the accurate origin of the truly co nverted neurons in vivo should be focused upon in future *** also arises the attention of replenishing the lost neurons from glia by gene therapies such as up-regulation of some transc ription factors or downregulation of PTBP1 or drug interfe rence therapies.

关键词： astrocytes neural stem cells neurodegenerative diseases neuron polypyrimidine tract binding protein 1 repair reprogramming small molecule transcription factor transdifferentiation

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Hydrogel loaded with bone marrow stromal cell-derived exosomes promotes bone regeneration by inhibiting inflammatory responses and angiogenesis

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World Journal of Stem Cells 2024年第5期16卷 499-511页

作者： shuai Zhang Chuan lu Sheng Zheng Guang Hong Division for International Collaborative and Innovative Dentistry Tohoku University Graduate School of DentistrySendai 980-8575MiyagiJapan School of Stomatology Zhejiang Chinese Medical UniversityHangzhou 310053Zhejiang ProvinceChina

BACKGROUND Bone healing is a complex process involving early inflammatory immune regu-lation,angiogenesis,osteogenic differentiation,and *** repair poses challenges for orthopedic surgeons,necessitating the search for efficient healing *** To investigate the underlying mechanism by which hydrogel-loaded exosomes derived from bone marrow mesenchymal stem cells(BMSCs)facilitate the process of fracture *** Hydrogels and loaded BMSC-derived exosome(BMSC-exo)gels were charac-terized to validate their *** vitro evaluations were conducted to assess the impact of hydrogels on various stages of the healing *** could recruit macrophages and inhibit inflammatory responses,enhance of human umbilical vein endothelial cell angiogenesis,and promote the osteogenic differen-tiation of primary cranial ***,the effect of hydrogel on fracture healing was confirmed using a mouse fracture *** The hydrogel effectively attenuated the inflammatory response during the initial repair stage and subsequently facilitated vascular migration,promoted the formation of large vessels,and enabled functional vascularization during bone *** effects were further validated in fracture *** We successfully fabricated a hydrogel loaded with BMSC-exo that modulates macrophage polarization and angiogenesis to influence bone regeneration.

关键词： Hydrogel Bone marrow mesenchymal stem cells Macrophage polarization Angiogenesis Bone regeneration

Progress on the antiferromagnetic topological insulator MnBi2Te4

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National Science Review 2024年第2期11卷 33-49页

作者： shuai Li Tianyu Liu Chang Liu Yayu Wang Hai-Zhou lu X.C.Xie Hefei National Laboratory International Center for Quantum Materials School of Physics Peking University Institute for Nanoelectronic Devices and Quantum Computing Fudan University Department of Physics Harbin Institute of Technology Shenzhen Institute for Quantum Science and Engineering and Department of Physics Southern University of Science and Technology(SUSTech) Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area(Guangdong) Shenzhen Key Laboratory of Quantum Science and Engineering International Quantum Academy Beijing Academy of Quantum Information Sciences Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-Nano Devices Department of Physics Renmin University of China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua University Frontier Science Center for Quantum Information

Topological materials, which feature robust surface and/or edge states, have now been a research focus in condensed maTher physics. They represent a new class of materials exhibiting nontrivial topological phases,and provide a platform for exploring exotic transport phenomena, such as the quantum anomalous Hall effect and the quantum spin Hall effect. Recently, magnetic topological materials have attracted considerable interests due to the possibility to study the interplay between topological and magnetic *** particular, the quantum anomalous Hall and axion insulator phases can be realized in topological insulators with magnetic order. MnBi2Te4, as the first intrinsic antiferromagnetic topological insulator discovered, allows the examination of existing theoretical predictions; it has been extensively studied, and many new discoveries have been made. Here we review the progress made on MnBi2Te4from both experimental and theoretical aspects. The bulk crystal and magnetic structures are surveyed first, followed by a review of theoretical calculations and experimental probes on the band structure and surface states, and a discussion of various exotic phases that can be realized in MnBi2Te4. The properties of MnBi2Te4thin films and the corresponding transport studies are then reviewed, with an emphasis on the edge state transport. Possible future research directions in this field are also discussed.

关键词： MnBi2Te4 magnetic topological insulator antiferromagnetic quantum anomalous Hall effect axion insulator

A GNSS Anti-Spoofing Technique Based on the Spatial Distribution Characteristic of the Residual Vectors

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Tsinghua Science and Technology 2024年第2期29卷 457-468页

作者： qi'an Wu Xiaowei Cui Mingquan lu Pengxiang Yang Peng Wu Department of Electronic Enginnering Tsinghua UniversityBeijing 100084China Xi’an Modern Control Technology Research Institute Xi’an 710065China

Anti-spoofing is becoming a crucial technique for applications with high navigation accuracy and reliability ***-spoofing technique based on Receiver Autonomous Integrity Monitoring(RAIM)is a good choice for most Global Navigation Satellite System(GNSS)receivers because it does not require any change to the hardware of the ***,the conventional RAIM method can only detect and mitigate a single spoofing *** improved RAIM methods can deal with more spoofing signals,but the computational complexity increases dramatically when the number of satellites in view increase or need additional *** paper proposes a new RAIM method,called the SRV-RAIM method,which has a very low computation complexity regardless of the number of satellites in view and can deal with any number of spoofing *** key to the new method is the spatial distribution characteristic of the Satellites'Residual Vectors(SRV).In replay or generative spoofing scenarios,the pseudorange measurements of spoofing signals are consistent,the residual vectors of real satellites and those of spoofing satellites have good separation characteristics in spatial *** on this characteristic,the SRV-RAIM method is proposed,and the simulation results show that the method can separate the real signals and the spoofing signals with an average probability of 86.55%in the case of 12 visible satellites,regardless of the number of spoofing *** to the conventional traversal-RAIM method,the performance is only reduced by 3.59%,but the computational cost is reduced by 98.3%,so most of the GNSS receivers can run the SRV-RAIM algorithm in time.

关键词： Global Navigation Satellite System(GNSS) anti-spoofing Receiver Autonomous Integrity Monitoring(RAIM) Satellites'Residual Vectors(SRV)

Constructing hierarchical arrays with core-shell metal oxides@metal coordination polymers for efficient and stable overall water splitting

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Nano Research 2024年第6期17卷 4882-4888页

作者： shuai qi Jinlian Liao Kunzhong Chen Senkai Li Jinwen Zhao Tianchi Huang Na Meng Hengpan Yang qi Hu Chuanxin He College of Chemistry and Environmental Engineering Shenzhen UniversityShenzhen 518060China

Developing non-precious metal-based bifunctional electrocatalysts capable for both hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)is essential to achieve efficient water electrolysis for mass hydrogen production,however it remains ***,we report the synthesis of hierarchical nanorod arrays comprising core-shell structured P-doped NiMoO4@NiFe-coordination polymer(denoted as P-NiMoO4@NiFeCP)as bifunctional electrocatalysts for water ***,we systematically investigate the influence of NiFeCP shell thickness on electrocatalytic activity,manifesting the presence of strong interfacial synergetic effect between P-NiMoO4 and NiFeCP for boosting both the HER and *** advantageous hierarchical architectures and unique core-shell structures,optimized P-NiMoO_(4)@NiFeCP-7.3(7.3 is the shell thickness in nm)requires overpotentials of merely 256 and 297 mV to yield a current density of 1000 mA·cm^(−2)for the HER and OER in 1 M KOH,*** importantly,it can serve as a bifunctional electrocatalyst for efficient and sustainable overall water electrolysis,delivering large current densities of 500 and 1000 mA·cm^(−2)at low cell voltages of 1.804 and 1.865 V,along with high stability of over 500 h at 1000 mA·cm−2,demonstrating the great potential of this electrocatalyst towards practical applications.

关键词： hydrogen evolution reaction oxygen evolution reaction overall water splitting non-precious metal-based electrocatalysts core-shell structures