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Stability and accuracy of central difference method for real-time dynamic substructure testing considering mass participation coefficient

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Earthquake Engineering and Engineering Vibration 2024年第3期23卷 625-636页

作者： zheng Lichang Xu Guoshan yang Ge Wang zhen yang Kaibo zheng zhenyun School of Civil Engineering Harbin Institute of TechnologyHarbin 150090China Key Lab of Structures Dynamic Behavior and Control Ministry of EducationHarbin Institute of TechnologyHarbin 150090China Key Lab of Intelligent Disaster Mitigation Ministry of Industry and Information TechnologyHarbin 150090China School of Civil Engineering and Architecture Wuhan University of TechnologyWuhan 430070China

For real-time dynamic substructure testing(RTDST),the influence of the inertia force of fluid specimens on the stability and accuracy of the integration algorithms has never been ***,this study proposes to investigate the stability and accuracy of the central difference method(CDM)for RTDST considering the specimen mass participation ***,the theory of the CDM for RTDST is ***,the stability and accuracy of the CDM for RTDST considering the specimen mass participation coefficient are ***,numerical simulations and experimental tests are conducted for verifying the effectiveness of the *** study indicates that the stability of the algorithm is affected by the mass participation coefficient of the specimen,and the stability limit first increases and then decreases as the mass participation coefficient *** most cases,the mass participation coefficient will increase the stability limit of the algorithm,but in specific circumstances,the algorithm may lose its *** stability and accuracy of the CDM considering the mass participation coefficient are verified by numerical simulations and experimental tests on a three-story frame structure with a tuned liquid damper.

关键词： real-time dynamic substructure testing central difference method stability mass participation coefficient tuned liquid damper

Variable Separated Solutions and Four-Dromion Excitations for (2+1)-Dimensional Nizhnik-Novikov-Veselov Equation

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Communications in Theoretical Physics 2008年第3期49卷 679-684页

作者： HU ya-Hong MA zheng-Yi zheng Chun-Long College of Science Zhejiang Lishui University Lishui 323000 China Shanghai Institute of Applied Mathematics and Mechanics Shanghai University Shanghai 200072 China

Using the mapping approach via the projective Riccati equations, several types of variable separated solutions of the （2＋1）-dimensional Nizhnik-Novikov-Veselov equation are obtained, including multiple-soliton solutions, periodic-soliton solutions, and Weierstrass function solutions. Based on a periodic-soliton solution, a new type of localized excitation, i.e., the four-dromion soliton, is constructed and some evolutional properties of this localized structure are briefly discussed.

关键词： Imapping approach Nizhnik-Novikov-Veselov equation variable separated solution dromion

Fatigue Crack Propagation Analysis of Orthotropic Steel Bridge with Crack Tip Elastoplastic Consideration

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Computer Modeling in Engineering & Sciences 2021年第5期127卷 549-574页

作者： Ying Wang zheng yan zhen Wang Jiangsu Key Laboratory of Engineering Mechanics Southeast UniversityNanjing211189China China Railway Major Bridge Reconnaissance and Design Institute Co. Ltd.Wuhan430056China

Due to the complex structure and dense weld of the orthotropic steel bridge deck(OSBD),fatigue cracks are prone to occur in the typical welding *** residual stress(WRS)will cause a plastic zone at the crack *** this paper,an elastoplastic constitutive model based on the Chaboche kinematic hardening model was introduced,and the extended finite element method(XFEM)was used to study the influence of material elastoplasticity and crack tip plastic zone on the law of fatigue crack *** judging the stress state of the residual stress field at the crack tip and selecting different crack propagation rate models to investigate the crack propagation law when plastic deformation was considered,the propagation path and propagation rate of fatigue crack of the OSBD were *** results show that,whether the residual stress field is considered or not,the plastic deformation at the crack tip will not cause the obvious closure of the fatigue crack at the U-rib toe during the crack propagation process,but will significantly affect the crack propagation *** material plasticity is considered,the propagation angle of fatigue crack at the U-rib toe basically remains unchanged along the short-axis direction of the initial crack,but is going up along the long-axis direction,and the crack tip plastic zone inhibits the propagation of the crack tip on one *** with linear elastic materials,the crack propagation law considering material plasticity is more consistent with that in actual bridge *** terms of the propagation rate,if the residual stress field is not considered,the fatigue crack propagation rate at U-rib toe with plasticity considered is slightly higher than that without plasticity considered,because plastic deformation will affect the amplitude of energy release *** considering the WRS field,the fatigue crack propagation rate at U-rib toe is increased due to the combined actions of plastic deformation and stress ratio R

关键词： Extended finite element fatigue crack propagation orthotropic steel bridge deck welding residual stress plastic deformation

CNKSR2 interactome analysis indicates its association with the centrosome/microtubule system

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Neural Regeneration Research 2025年第8期20卷 2420-2432页

作者： Lin Yin yalan Xu Jie Mu Yu Leng Lei Ma Yu zheng Ruizhi Li Yin Wang Peifeng Li Hai Zhu Dong Wang Jing Li Institute for Translational Medicine The Affiliated Hospital of Qingdao UniversityMedical CollegeQingdao UniversityQingdaoShandong ProvinceChina School of Basic Medicine Qingdao UniversityQingdaoShandong ProvinceChina College of Life Sciences and School of PharmacyMedical CollegeQingdao UniversityQingdaoShandong ProvinceChina Department of Urology Qingdao Municipal Hospital Affiliated to Qingdao UniversityQingdaoShandong ProvinceChina

The protein connector enhancer of kinase suppressor of Ras 2(CNKSR2),present in both the postsynaptic density and cytoplasm of neurons,is a scaffolding protein with several protein-binding *** of the CNKSR2 gene have been implicated in neurodevelopmental disorders,particularly intellectual disability,although the precise mechanism involved has not yet been fully *** has demonstrated that CNKSR2 plays a role in facilitating the localization of postsynaptic density protein complexes to the membrane,thereby influencing synaptic signaling and the morphogenesis of dendritic ***,the function of CNKSR2 in the cytoplasm remains to be *** this study,we used immunoprecipitation and high-resolution liquid chromatography-mass spectrometry to identify the interactors of *** a combination of bioinformatic analysis and cytological experiments,we found that the CNKSR2 interactors were significantly enriched in the proteome of the *** also showed that CNKSR2 interacted with the microtubule protein DYNC1H1 and with the centrosome marker *** colocalization analysis confirmed the centrosomal localization of *** we downregulated CNKSR2 expression in mouse neuroblastoma cells(Neuro 2A),we observed significant changes in the expression of numerous centrosomal *** manipulation also affected centrosome-related functions,including cell size and shape,cell proliferation,and ***,we found that CNKSR2 interactors were highly enriched in de novo variants associated with intellectual disability and autism spectrum *** findings establish a connection between CNKSR2 and the centrosome,and offer new insights into the underlying mechanisms of neurodevelopmental disorders.

关键词： autism spectrum disorder centrosome CNKSR2 intellectual disability interactome mass spectrometry microtubule neurodevelopmental disease protein complexes protein-protein interactions

Effect of purification pretreatment on the recovery of magnetite from waste ferrous sulfate

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International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 891-897页

作者： Wang Yu Ying-lin Peng ya-jie zheng School of Metallurgy and Environment Central South University School of Chemistry and Environmental Engineering Hunan City University

The present study was conducted to elucidate the influence of impurities in waste ferrous sulfate on its recovery of magnetite. Ferrous sulfate solution was purified by the addition of Na OH solution to precipitate impurities, and magnetite was recovered from ferrous sulfate solution without and with purification pretreatment. Calcium hydroxide was added to the solution of ferrous sulfate as a precipitator. A mixed product of magnetite and gypsum was subsequently obtained by air oxidation and heating. Wet-milling was performed prior to magnetic separation to recover magnetite from the mixed products. The results show that with the purification pretreatment, the grade of iron in magnetite concentrate increased from 62.05% to 65.58% and the recovery rate of iron decreased from 85.35% to 80.35%. The purification pretreatment reduced the conglutination between magnetite and gypsum, which favors their subsequent magnetic separation. In summary, a higher-grade magnetite with a better crystallinity and a larger particle size of 2.35 μm was obtained with the purification pretreatment.

关键词： ferrous sulfate titanium dioxide purification magnetite magnetic separation

Influence of silicon on the microstructures, mechanical properties and stretch-flangeability of dual phase steels

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International Journal of Minerals,Metallurgy and Materials 2014年第8期21卷 755-765页

作者： Le-yu Zhou Dan Zhang ya-zheng Liu School of Materials Science and Engineering University of Science and Technology Beijing

Uniaxial tension tests and hole-expansion tests were carried out to determine the influence of silicon on the microstructures, mechanical properties, and stretch-flangeability of conventional dual-phase steels. Compared to 0.03wt% silicon, the addition of 1.08wt% silicon induced the formation of finer ferrite grains （6.8μm ） and a higher carbon content of martensite （Cm≈ 0.32wt%）. AS the silicon level increased, the initial strain-hardening rate （n value） and the uniform elongation increased, whereas the yield strength, yield ratio, and stretch-flangeability decreased. The microstructures were observed after hole-expansion tests. The results showed that low carbon content martensite （Cm ≈ 0.19wt%） can easily deform in coordination with ferrite. The relationship between the mechanical properties and stretch-flangeability indicated that the steel with large post-uniform elongation has good stretch-flangeability due to a closer plastic incom- patibility of the ferrite and martensite phases, which can effectively delay the production and decohesion of microvoids.

关键词： dual-phase steel silicon content mechanical properties microstructure strain hardening

The Real-Time Simulation of Doppler Spread in Wireless Mobile Environment by RF Circuits

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Chinese Journal of Electronics 2015年第4期24卷 837-843页

作者： LI zhen ZHU Xiang JI Wenli zheng Guoxin Key Laboratory of Specialty Fiber Optics and Optical Access Networks Shanghai University Technical Center of Shanghai Shentong Metro Group Co .Ltd

The time-varying characteristic of wireless channel under the high-speed mobile environments in tunnels causes the Doppler spread to the transmitted signals,which affects the performance of wireless communication systems. The real-time Doppler effect simulation methodology directly based on Radio frequency(RF) circuits is proposed to simulate different Doppler spread effects in real environments. Mixers and a Digital-to-analog(DA)converter circuit are utilized to spread the spectrum of RF signals. A PC platform with the interface written in C#is configured to control the spectrum spread *** radio channel emulator with the proposed methodology can replace the expensive fading simulating instruments with only 25.1ns system delay. Such an emulator has been applied to test the Multi-carrier wireless information local loop(McW i LL) wireless vehicle communication system in the laboratory to meet the requirement of metro Communication based train control(CBTC) system.

关键词： Doppler spread Channel simulation Circuits Tunnel Metro system

A New Steroid from Polygonum nodosum Pers

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Chinese Chemical Letters 2003年第2期14卷 176-178页

作者： Shang zhen zheng Tong SHEN 等 CollegeofChemistryandChemicalEngineering NorthwestNormaluniversityLanzhou730070 NationalLaboratoryofAppliedOrganicChemistry instituteofOrganicChemistryLanzhouUniversityLanzhou730

A new steroid named as Zhonghualiaoine I (1) was isolated from Polygonum nodosum Pers (Chinese name 揨honghualiao? Berberidaceae). Its structure was deduced on the basis of its spectral data.

关键词： Polygonum nodosum isolation elucidation.

MEASUREMENT AND ANALYSIS OF LASER GENERATED RAYLEIGH AND LAMB WAVES CONSIDERING ITS PULSE DURATION

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Acta Mechanica Solida Sinica 2015年第5期28卷 441-452页

作者： zhen Zhang Yongdong Pan Yi Xiao zheng Zhong School of Aerospace Engineering and Applied Mechanics Tongji University

In this article, laser generated Rayleigh and Lamb waves are studied by taking into account its pulse duration. The physical model and theoretical solution are presented to predict the corresponding waveforms for aluminum samples under the ablation generation regime. The waveforms of the excited Rayleigh and Lamb waves by laser with selected pulse duration were measured by laser interferometer and analyzed theoretically, and the agreement between measurement and analysis is demonstrated for the validation of the theoretical model and solution. The broadening of the Rayleigh wave and the disappearing of high order Lamb wave modes can be found with the increase of the pulse duration by the laser ultrasonic technique.

关键词： Rayleigh wave Lamb wave pulse duration laser ultrasonic technique