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Investigation on the vortical structures by the Liutex method in turbulent channels at Re_(τ)=180 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： zhang-dan yu Shang Jiang Hai-dong yu Bi-yu Pang Xin Dong yi-qian Wang School of Mathematical Sciences Soochow UniversitySuzhou215006China Beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction *** and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various *** this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well *** conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted *** in wall units of W^(+)=20 and height-width ratio ofγ=0.5 are selected for both riblet *** with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag *** obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further *** compare turbulent statistics of the scalloped riblet case with those of the triangular riblet *** mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and Liutex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the *** also compare the pre-multiplied spectra of streamwise velocity and streamwise Liutex component for the three cases to investigate the energy distribution and characteristics of Liutex *** Liutex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be bene

关键词： Liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

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Simulating the GRF of Humanoid Robot Vertical Jumping Using a Simplified Model with a Foot Structure for Foot Design

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Journal of Bionic Engineering 2024年第1期21卷 112-125页

作者： Chuanku yi Xuechao Chen yu zhang zhangguo yu Haoxiang Qi Yaliang Liu Qiang Huang School of Mechatronical Engineering Beijing Institute of TechnologyZizhuyaunHaidianBeijing 100081China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of Tec

There are many theories and tools for human or robot motion simulation,but most of them require complex *** LNZN model(a simplified model named by the proposers)simplifies the human model and facilitates simulation of the Ground Reaction Force(GRF)of body landing by spring damping model and ignoring joint rotation movements,which can reduce the amount of computation *** this paper,the LNZN model of human running is selected as the basis and is modified to obtain the LNZN model of a robot,which expands the application of the LNZN *** to the structure of the human foot,a foot structure is then added to the simplified model to reduce the *** also applied driving forces to the new model to simulate the whole high jump motion of the robot to expand the functions of the LNZN *** obtained GRF data were anastomotic to the actual experimental *** addition,the effects of variables,such as the mass,hardness,and damping,of the foot on the GRF at the moment of landing were also ***,based on the guidelines obtained for the design of the robot’s foot structure,we fabricated new robot’s feet and installed them on the actual robot and achieved a better cushioning effect than the original foot in experiments.

关键词： LNZN model-GRF simulation Humanoid foot structure Foot parameters

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Accuracy evaluation for in-situ machining reference points binocular measurement based on credibility probability

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Chinese Journal of Aeronautics 2024年第1期37卷 472-486页

作者： Binchao yu Wei LIU Yanze zhang Dazhi MA Zhenyuan JIA yi yuE Jiabo zhang Key Laboratory for Precision and Non-Traditional Machining Technology of the Ministry of Education Dalian University of TechnologyDalian 116024China Beijing Spacecrafts China Academy of Space TechnologyBeijing 100081China

Passive binocular measurement systems are being increasingly utilized in the in-situ industries of automobiles,aviation,and aerospace,*** to their excellent qualities of accuracy,efficiency,and cost *** the barrier of evaluating the accuracy of measured objects resulted from the unequal equivalent focal length and quantization of pixels,has limited their further development and application of high requirements for in-situ machining,e.g.,the measurement of machining reference points for the positioning of robotic drilling in aerospace *** this paper,an accuracy evaluation method is proposed to address the ***,the unequal equivalent focal length is considered to improve the accuracy of 3D ***,the credibility probability model is developed to calculate the probability of the observed error in the public view of the binocular measurement system and indicates the direction of ***,the in-situ experiment is carried out to validate the method within the effective public view range of 300 mm×300 *** experiment results show that the RMSs of observed errors are superior to 0.035 mm,and the credibility probabilities are all higher than 0.91;the maximum 3D reconstruction accuracy improvement is 60.3%,with the error reduced from 0.078 mm to 0.031 mm.

关键词： Aerospace manufacturing Binocular vision Credibility probability Pixel quantization Unequal equivalent focal length

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Numerical investigations of the interactions between bubble induced shock waves and particle based on OpenFOAM

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Journal of Hydrodynamics 2024年第2期36卷 355-362页

作者： Jia-xin yu Jin-sen Hu yu-hang Liu yi-fan Liu Dan Gao yu-ning zhang Key Laboratory of Power Station Energy Transfer Conversion and System Ministry of EducationSchool of Energy Power and Mechanical EngineeringNorth China Electric Power UniversityBeijing102206China

The presence of particles and the shock waves generated by the cavitation bubbles can significantly affect the safety and the performance of hydrodynamic *** the present paper,the shock waves generated by cavitation bubble collapsing near the particle are numerically investigated based on the OpenFOAM together with the numerical schlieren for the shock wave *** numerical results reveal that the stand-off distance is one of the paramount factors affecting the interactions between the particle and the shock *** different kinds of shock waves(e.g.,bubble-inception,jet formation,particle reflected and jet-split shock waves)are observed during the bubble collapsing near the *** stand-off distance smaller than 0.5 or larger than 1.1,the maximum pressure at particle surface generated by the bubble growth can surpass those of the collapse stage.

关键词： Particle-bubble interaction shockwaves jetdynamics

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4~18 GHz超宽带行波管输能系统设计

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真空电子技术 2024年第2期 85-89页

作者：曹绅崔建玲孟晓君张依雨张雪利张凯周忠正北京真空电子技术研究所北京100015 电子科技大学四川成都610054

为满足新一代电子对抗装备对跨频带超宽带行波管的需求,本文针对4~18 GHz超宽带大功率行波管输能系统开展了匹配优化设计和功率容量分析研究。从同轴窗、同轴输能结构及输能结构与高频结构匹配等几方面综合优化,设计出输入驻波比优于1.5... 详细信息

为满足新一代电子对抗装备对跨频带超宽带行波管的需求,本文针对4~18 GHz超宽带大功率行波管输能系统开展了匹配优化设计和功率容量分析研究。从同轴窗、同轴输能结构及输能结构与高频结构匹配等几方面综合优化,设计出输入驻波比优于1.53、输出驻波比优于1.55的输能系统,与测试结果对比表明设计方法合理,输能系统和器件匹配成功;针对输出系统的功率容限问题,从峰值功率和平均功率两方面分析了输能窗的电可靠性和热可靠性,制管实测结果表明,该输能系统能够满足行波管应用要求。

关键词：行波管超宽带输能系统匹配设计功率容量

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Controllable nucleation and deformation of skyrmions on surface of magnetic nanotubular monolayer

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Rare Metals 2024年第7期43卷 3250-3259页

作者： Xin-Xin zhang Chen-yu zhang yi-Xin Xing Chao Man Jiao Liu Yong Hu Department of Physics College of SciencesNortheastern UniversityShenyang 110819China School of Materials and Mineral Resources Engineering Universiti Sains MalaysiaEngineering Campus14300 Nibong TebalPenangMalaysia State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang110819China

Magnetic skyrmions emerge when the energy of ferromagnetic exchange interaction promoting parallel alignment of spins enters in competition with energies favoring non-collinear alignment of spins such as Dzy aloshinskii-Moriya interaction(DMI),long-rang dipole-dipole interaction(DDI),or higher-order exchange *** perform an unbiased Monte Carlo simulation to study the DMI-based skyrmion nucleation and stabilization on the surface of magnetic nanotubular monolayer controlled by tuning constants of DDI(g) and next-nearest-neighbor antiferromagnetic exchange interaction(j') with appropriate *** g and j',the loosely distributed skyrmions initially nucleate on the surface of nanotube approaching to the magnetic field(h) direction with increasing h in the intermediate ***,the skyrmion size,shape,density,distribution and crystal structure,as well as its driven field range,are tailored by g and j'.This work demonstrates the skyrmion nucleation mechanisms in three-dimensional magnetic nanostructures with curvature effect and multiple interactions,serving as a benchmark for a guide to experimentalists for preparation of samples in magnetic skyrmion states.

关键词： Magnetic nanotube Magnetic skyrmion Dzyaloshinskii-Moriya interaction Dipole-dipole interaction Monte Carlo simulation

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Protein neddylation and its role in health and diseases

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Signal Transduction and Targeted Therapy 2024年第5期9卷 1869-1904页

作者： Shizhen zhang Qing yu Zhijian Li Yongchao Zhao yi Sun Department of Breast Surgery the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Cancer Institute(Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education)the Second Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Institute of Translational Medicine Zhejiang University School of MedicineHangzhou 310029China Department of Thyroid Surgery Zhejiang Cancer HospitalInstitute of Basic Medicine and Cancer(IBMC)Chinese Academy of SciencesHangzhou 310022China Key Laboratory of Head&Neck Cancer Translational Research of Zhejiang Province Hangzhou 310022China Department of Hepatobiliary and Pancreatic Surgery Zhejiang University School of MedicineHangzhou 310029China Zhejiang Provincial Key Laboratory of Pancreatic Disease The First Affiliated HospitalZhejiang University School of MedicineHangzhou 310029China Zhejiang University Cancer Center Hangzhou 310029China Leading Innovative and Entrepreneur Team Introduction Program of Zhejiang Hangzhou 310024China Research Center for Life Science and Human Health Binjiang Institute of Zhejiang UniversityHangzhou 310053China

NEDD8(Neural precursor cell expressed developmentally downregulated protein 8)is an ubiquitin-like protein that is covalently attached to a lysine residue of a protein substrate through a process known as neddylation,catalyzed by the enzyme cascade,namely NEDD8 activating enzyme(E1),NEDD8 conjugating enzyme(E2),and NEDD8 ligase(E3).The substrates of neddylation are categorized into cullins and non-cullin *** of cullins activates CRLs(cullin RING ligases),the largest family of E3 ligases,whereas neddylation of non-cullin substrates alters their stability and activity,as well as subcellular ***,the neddylation pathway and/or many neddylation substrates are abnormally activated or over-expressed in various human diseases,such as metabolic disorders,liver dysfunction,neurodegenerative disorders,and cancers,among ***,targeting neddylation becomes an attractive strategy for the treatment of these *** this review,we first provide a general introduction on the neddylation cascade,its biochemical process and regulation,and the crystal structures of neddylation enzymes in complex with cullin substrates;then discuss how neddylation governs various key biological processes via the modification of cullins and non-cullin *** further review the literature data on dysregulated neddylation in several human diseases,particularly cancer,followed by an outline of current efforts in the discovery of small molecule inhibitors of neddylation as a promising therapeutic ***,few perspectives were proposed for extensive future investigations.

关键词： NEDD8 attached attractive

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Tribological and Corrosion Properties of the CoCrAlYTaSiC-xCNTs Coatings Deposited by Laser Cladding

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 726-738页

作者： Hai Zhao yi Ding Wei Gao Bo yu Jinghui Li Mingya zhang School of Material Science and Engineering Anhui University of TechnologyMaanshan243002China Maanshan Iron&Steel Co. LtdMaanshan243000China Applied Technology Research Institute Jiujiang Vocational UniversityJiujiang332000China School of Metallurgical Engineering Anhui University of TechnologyMaanshan243002China

The MCrAlY coating has been potential candidate for the parts applied in friction and corrosion conditions, and CNTs (carbon nanotubes) are expected to improve the service performance of coatings owing to high lubrication and low chemical reactivity. In this work, a systematic investigation on the tribological and corrosion properties of CoCrAlYTaSiC-xCNTs coatings deposited by laser melting was analyzed. Results showed that the coatings had good-quality without typical metallurgical defects. The CNTs addition homogenized and refined the microstructure of coating, and also improved the tribological and corrosion properties. As the CNTs content changed from 0 to 4 wt%, the wear rate of coating decreased from 16.23 × 10^(-3) to 7.58 × 10^(-3) mg m^(−1), the jcorr of coating decreased from 4.13 × 10^(-4) to 1.23 × 10^(-4) A cm^(−2), and the Rct values increased from 12.69 to 25.07 Ω cm2.

关键词： MCrAlY coating Laser melting deposition Friction Electrochemical corrosion

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Non-synchronous vibration of rotor blade in a six-stage transonic compressor

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Chinese Journal of Aeronautics 2024年第8期37卷 36-48页

作者： Ronghui CHENG Zhuo WANG Huawei yu Lin DU yi zhang Xiaofeng SUN Aeroengine Research Institute Beihang UniversityBeijing 102206China School of Energy and Power Engineering Beihang UniversityBeijing 102206China

This paper presents an experimental study on the Non-Synchronous Vibration(NSV)in a six-stage transonic *** first part of the paper describes the NSV phenomenon of Rotor 1,which occurs when both Stator 1(S1)and Stator 2(S2)or S1 only are *** measurements and analysis are carried out for the former case through the unsteady wall pressure and the Blade Strain(BS).The spinning mode theory used in the rotor/stator interaction noise is employed to explain the relation between the circumferential wave number of the aerodynamic disturbance and the Nodal Diameter(ND)of the blade *** variations of the vibration amplitudes of different blades and the Inter-Blade Phase Angles(IBPAs)at different moments suggest that the evolution of NSV is a highly nonuniform phenomenon along the circumferential *** addition,the difference between the wall-pressure spectra generated by the NSV and the classic flutter has been *** the second part,the variations of aerodynamic loading due to the adjustment of the staggers of the Inlet Guide Vane(IGV),S1 and S2 have been *** is found that closing S1 only can result in a great fluctuation to the performance of the front stages,which might be detrimental to the flow organization and increase the risk of *** contrast,the effect of closing S2 only on the performance of the first two stages appears to be slighter relatively.

关键词： Transonic compressor Non-synchronous vibration Modal analysis Aerodynamic loading Nodal diameter

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Nanomaterial Assisted Exosome Analysis Using Mass Spectrometry

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Chemical Research in Chinese Universities 2024年第2期40卷 237-254页

作者： zhang yi ZHOU Bokai LI Qiuning JIN Mingshi BAI yu Beijing National Laboratory for Molecular Sciences Key Laboratory of Bioorganic Chemistry and Molecular Engineering of Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing100871P.R.China Department of Chemistry Yanbian UniversityYanji133002P.R.China

Exosomes,extracellular vesicles(EVs)that play crucial roles in biological processes,have emerged as attractive targets for noninvasive disease diagnosis and *** spectrometry(MS)offers high sensitivity,high throughput,and excellent qualification and quantification capacity,which is the ideal approach for exosome ***’unique physiochemical properties,controllable morphology,and large surface area make them promising in biological sample pretreatment and *** contributed diverse functions to the exosome MS analysis,encompassing substrates for exosome isolation and cargos enrichment,matrices for laser desorption/ionization(LDI),read-out signals and supporters for signal amplification strategies,*** this review,recent progress in the applications of nanomaterial in the exosome MS analysis was summarized and a comprehensive discussion on the challenges and perspectives was proposed for the development of an advancing analysis approach of exosomes for the accurate diagnosis and monitoring of diseases.

关键词： Exosome Nanomaterial Enrichment Matrix Mass spectrometry

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