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Numerical simulation of the seismic behavior of self-centering steel beam-column connections with bottom flange friction devices

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Earthquake Engineering and Engineering Vibration 2011年第2期10卷 229-238页

作者： guo Tong song Lianglong zhang guodong Key Laboratory of Concrete and Prestressed Concrete Structure Ministry of Education Southeast Univ. Nanjing 210096 China

A new type of steel moment resisting frame with bottom flange friction devices （BFFDs） has been developed to provide self-centering capacity and energy dissipation, and to reduce permanent deformations under earthquakes. This paper presents a numerical simulation of self-centering beam-column connections with BFFDs, in which the gap opening/closing at the beam-column interfaces is simulated by using pairs of zero-length elements with compression-only material properties, and the energy dissipation due to friction is simulated by using truss elements with specified hysteretic behavior. In particular, the effect of the friction bolt bearing against the slotted plate in the BFFDs was modeled, so that the increase in lateral force and the loss of friction force due to the bolt bearing could be taken into account. Parallel elastic-perfectly plastic gap （ElasticPPGap） materials in the Open System for Earthquake Engineering Simulation （OpenSees） were used with predefined gaps to specify the sequence that each bolt went into the bearing and the corresponding increase in bending stiffness. The MinMax material in OpenSees is used to specify the minimum and maximum values of strains of the ElasticPPGap materials. To consider the loss of friction force due to bok bearing, a number of parallel hysteretic materials were used, and the failure of these materials in sequence simulated the gradual loss of friction force. Analysis results obtained by using the proposed numerical model are discussed and compared with the test results under cyclic loadings and the seismic loading, respectively.

关键词： numerical simulation post tensioned self-centering moment resisting steel frame bottom flange frictiondevice bolt bearing

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Use of bionic inspired surfaces for aerodynamic drag reduction on motor vehicle body panels

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 543-551页

作者： Xiao-wen song guo-geng zhang Yun WANG Shu-gen HU Department of Mechanical Engineering Zhejiang University Hangzhou 310027 China

Inspired by the successful applications of biological non-smoothness,we introduced bionic non-smooth surfaces as appendices into vehicle body design,aiming to further reduce aerodynamic *** size range of the non-smooth units with pits and grooves was determined according to our analysis with the mechanisms underlying non-smooth unit mediated aerodynamic drag *** bionic non-smooth units reported here were designed to adapt the structure of a given vehicle body from the point of boundary layer control that reduces the burst and the loss of turbulent kinetic *** engine cover lid and vehicle body cap were individually treated with the non-smooth units,and the treated vehicles were subjected to aerodynamic drag coefficient simulation tests using the computational fluid dynamics(CFD) analysis *** simulation results showed that,in comparison with smooth surfaces,properly designed non-smooth surfaces can have greater effects on drag *** mechanism underlying drag reduction mediated by non-smooth surfaces was revealed by further analyses,in which the effects of non-smooth and smooth surfaces were directly compared.

关键词： Computational fluid dynamics(CFD) Bionics Non-smooth surface Aerodynamic drag reduction Vehicle body

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Magnesium single-atom catalysts with superbasicity

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Science China Chemistry 2023年第6期66卷 1737-1743页

作者： Xiang-Bin Shao Yao Nian song-song Peng guo-song zhang Meng-Xuan Gu You Han Xiao-Qin Liu Lin-Bing Sun State Key Laboratory of Materials-Oriented Chemical Engineering Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

Magnesium-related solid bases have long been considered catalysts with weak or medium *** we report the fabrication of Mg single-atom catalysts with superbasicity for the first time.A sublimation-migration-anchoring strategy is employed,in which the Mg net is sublimated,transported by Ar,and trapped by defective graphene(producing Mg_(1)/G).Simulated and experimental results demonstrate that Mg single atoms are anchored on graphene in tetra-coordination,and Mg single atoms cooperating with C atoms give superbasicity,which differs from conventional alkali/alkaline earth metal oxides with basicity originating from O *** new solid base is highly active in the synthesis of dimethyl carbonate through transesterification of ethylene carbonate with methanol,which is usually catalyzed by strong *** turnover frequency value reaches 99.6 h^(-1) on Mg_(1)/G,which is much higher than that of traditional Mg-related counterparts(1.0–5.6 h^(-1))and even superior to that of typical Na and K-related solid superbases(29.8–36.2 h^(-1))under similar conditions.

关键词： solid superbase single Mg atoms heterogeneous catalysts transesterification reaction

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Fabrication of porous Zn_(2)TiO_(4)-ZnO microtubes and analysis of their acetone gas sensing properties

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Rare Metals 2021年第6期40卷 1528-1535页

作者： Xiao-Yan Chen Xin-Zhen Wang Feng-Jun Liu guo-song zhang Xiao-Jie song Jian Tian Hong-Zhi Cui School of Materials Science and Engineering Shandong University of Science and TechnologyQingdao 266590China Shandong Province Key Laboratory of Mine Mechanical Engineering Shandong University of Science and TechnologyQingdao 266590China

Porous Zn2 Ti04-ZnO microtubes have been successfully fabricated using chemical precipitation followed by a calcination process using a carbon fiber *** porous Zn_(2)TiO_(4)-ZnO micro tubes with a diameter of~4μm consisted of Zn_(2)TiO_(4) and ZnO *** displayed worm-like pore *** fibers played an important role during the porous Zn_(2)TiO_(4)-ZnO microtube formation *** porous and hollow structure of Zn_(2)TiO_(4)-ZnO provided abundant active sensing sites and channels for gas adsorption and *** porous Zn_(2)TiO_(4)-ZnO microtubes exhibited improved gas sensing properties for acetone when compared with pure *** Zn_(2)TiO_(4)-ZnO sensor response was 33.4 for 100μg·ml^(-1) acetone at the optimum operating temperature(370℃).This was~2.7 times higher than that of pure ***,the as-prepared porous Zn_(2)TiO_(4)-ZnO microtubes displayed sufficient long-term acetone stability and *** showed the potential application for acetone *** enhanced Zn_(2)TiO_(4)-ZnO gas sensing properties are due to the unique heterogeneous and porous structure,which was analyzed using the porous and band structure.

关键词： Zn_(2)TiO_(4) Zinc oxide Porous Heterostructure Sensors

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Using the Box-Behnken Response Surface Method to Optimize the Preparation and Characterization of Lavender and Fennel Volatile oilβ-cyclodextrin Form Inclusion Complex

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World Journal of Traditional Chinese Medicine 2018年第2期4卷 54-61页

作者： Yuan-Yuan Liu guo-song zhang Guang-Wei Zhu Ai-Ni-Wa-Er Aikemu Jia-Jia Ai Dong-Xun Li The National Pharmaceutical Engineering Center for Solid Preparation in Chinese Herbal Medicine Jiangxi University of Traditional Chinese Medicine Chinese Medicine Research Institute Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences Basic Medical College Xinjiang Medical University

Objective:The objective of this study is to study the best inclusion technology of Lavender-and fennel-mixed volatile oil by beta?cyclodextrin(β-CD) and characterize the final product ***:Using the saturated water solution method,the volatile β-CD inclusion complex was *** effect of volatile oil weight ratio,inclusion temperature and inclusion time on the inclusive quality was studied by measuring the yield of inclusion and inclusion rate of volatile oil as evaluation *** preparation method of inclusion complex was then optimized by the Box-Behnken response surface *** inclusion complex was characterized by ultraviolet spectrophotometry,thin-layer chromatography,thermogravimetry and differential thermal analysis,and the microscopic imaging ***:The optimized conditions were the weight ratio of β-CD to volatile oil was 8.13:1(g/ml).The inclusion temperature was 44°*** inclusion time was 1 ***:We were able to produce an inclusion complex with high inclusion rate of volatile oil and high yield of inclusion using the preparation method mentioned ***,the method can also improve the stability of volatile oil in abnormal savda *** study can provide a good reference for the development of new preparations.

关键词： Fennel inclusion complex lavender response surface method volatile oil β-cyclodextrin

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Molecular dynamics simulations of helium transport through inorganic mineral nanopores

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Science China Earth Sciences 2025年第1期68卷 237-252页

作者： Dandan song Ping GUAN Chi zhang Jiahao REN School of Earth and Space Sciences Peking University

Helium transport through nanoscale inorganic mineral pores and pore throats is essential for its overall migration. To elucidate helium's transport dynamics within nanopores, we employed equilibrium and non-equilibrium molecular dynamics simulations to investigate helium's static self-diffusion and pressure-driven flow in quartz slit-shaped nanopores. We also introduced water and various gases, including hydrogen, methane, ethane, nitrogen, and carbon dioxide, into the nanopores to assess their influence on helium transport. Our findings indicate minimal helium adsorption on quartz pore surfaces. Under conditions where the pore size is less than 5 nm and the pressure under 10 MPa, environmental factors markedly influence helium diffusion. Large pore sizes, high temperatures, and low gas pressures enhance helium desorption and facilitate faster diffusion. We observed a positive correlation between helium flow velocity and factors such as pore size, pressure gradient, and surface smoothness of the pores. Notably, the presence of pore water and carrier gases in quartz nanopores, which diffuse more slowly than helium, tends to reduce helium surface adsorption and slow its diffusion. Among the carrier gases studied, nitrogen showed similar adsorption capacity, diffusivity, and stability to helium, while carbon dioxide displayed the highest adsorption capacity and the slowest diffusion rate, markedly differing from helium. Based on the simulation results, we concluded that water and carrier gases primarily function as transport mediums in helium migration, moving together with helium. Nitrogen, which shares similar properties with helium, effectively assists in this co-migration process. Conversely, carbon dioxide, due to its high adsorption capacity and slow diffusion, tends to be lost during co-migration. As a result, gas reservoirs with high nitrogen levels and low carbon dioxide levels are more likely to have higher helium concentrations. Additionally, the smaller por

关键词： Helium transport Slit nanopores Molecular dynamics simulations Diffusion Flow carriers

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ImSpiRE: image feature-aided spatial resolution enhancement method

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Science China Life Sciences 2025年第1期68卷 272-283页

作者： Yuwei Hua Yizhi zhang Zhenming guo Shan Bian Yong zhang State Key Laboratory of Cardiovascular Diseases and Medical Innovation Center Institute for Regenerative MedicineDepartment of NeurosurgeryShanghai East HospitalShanghai Key Laboratory of Signaling and Disease ResearchFrontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji University

The resolution of most spatially resolved transcriptomic technologies usually cannot attain the single-cell level, limiting their applications in biological discoveries. Here, we introduce ImSpiRE, an image feature-aided spatial resolution enhancement method for in situ capturing spatial transcriptome. Taking the information stored in histological images, ImSpiRE solves an optimal transport problem to redistribute the expression profiles of spots to construct new transcriptional profiles with enhanced resolution, together with extending the gene expression profiles into unmeasured regions. Applications to multiple datasets confirm that ImSpiRE can enhance spatial resolution to the subspot level while contributing to the discovery of tissue domains, signaling communication patterns, and spatiotemporal characterization.

关键词： spatial transcriptome histological images spatial resolution enhancement

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Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期68卷 26-34页

作者： Yutao zhang Juan Li Wei-Hong Zhu Zhiqian guo Shanghai Key Laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State Key Laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

关键词： chemiluminescnece sequence-activation in-vivo bioimaging cyclic peroxide

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Effects of TiB_2+TiC content on microstructure and wear resistance of Ni55-based composite coatings produced by plasma cladding

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Transactions of Nonferrous Metals Society of China 2019年第1期29卷 132-142页

作者： Xin-jie zhang Hong-zhi CUI Jia-feng WANG guo-song zhang Yu-qiao ZHAO Kang SUN School of Materials Science and Engineering Shandong University of Science and Technology Qingdao 266590 China

TiB2-TiC reinforced Ni55 matrix composite coatings were in-situ fabricated via plasma cladding on steels using Ti, B4C, and Ni55 as precursor materials at different proportions. Effects of TiB2+TiC content of ceramics phase on the microstructure and wear resistance were studied. The results showed that ceramic phases TiB2 and TiC were in-situ synthesized by plasma cladding, and the ceramic phase content significantly affected tribological performance and the wear mechanism of coatings under different loads. The composite ceramics protected coatings from further delamination wear by crack-resistance under a load of 30 N. Severe abrasive wear and adhesive wear were prevented when the load increased to 60 N because of the high hardness and strength of ceramic phases. Moreover, a compacted layer appeared on the wear surface of coatings with high content of ceramic phases, which effectively decreased the friction coefficient and wear rate. The TiB2-TiC composite ceramics significantly improved the wear performance of metal matrix composite coatings by different mechanisms under loads of 30 and 60 N.

关键词： metal matrix composite coating plasma cladding microstructure tribological behavior wear mechanism

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Cross-reactivity of hypervariable region 1 chimera of hepatitis C virus

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World Journal of Gastroenterology 2003年第6期9卷 1256-1260页

作者： Bing-Shui Xiu Shi-Gan Ling Xiao-guo song He-Qiu zhang Kun Chen Cui-Xia Zhu Laboratory of Molecular Virology,Institute of Basic Medical Sciences,Academy of Military Medical Sciences,Beijing 100850,China Laboratory of Molecular Virology Institute of Basic Medical Sciences Academy of Military Medical Sciences Beijing 100850 P.R.China.

AIM: To analyze the amino acid sequences of hypervariable region 1 (HVR1) of HCV isolates in China and to construct a combinatorial chimeric HVR1 protein having a very broad high cross-reactivity.METHODS: All of the published HVR1 sequences from China were collected and processed with a computer *** representative HVR1's sequences were formulated based on a consensus profile and homology within certain subdivision. A few reported HVR1 mimotope sequences were also included for a broader representation. All of them were cloned and expressed in ***. The cross-reactivity of the purified recombinant HVR1 antigens was tested by ELISA with a panel of sera from HCV infected patients in *** of them were further ligated together to form a combinatorial HVR1 chimera.RESULTS: Altogether 12 HVR1s were selected and expressed in E. coli and purified to homogeneity. All of these purified antigens showed some cross-reactivity with sera in a 27 HCV positive panel. Recombinant HVR1s of No. 1, 2, 4, and 8# showing broad cross-reactivities and complementarity with each other, were selected for the ligation elements. The chimera containing these 4 HVR1s was highly expressed in E. coli. The purified chimeric antigen could react not only with all the HCV antibody positive sera in the panel but also with 90/91 sera of HCV -infected patients.CONCLUSION: The chimeric antigen was shown to have a broad cross-reactivity. It may be helpful for solving the problem caused by high variability of HCV, and in the efforts for a novel vaccine against the virus.

关键词：丙型肝炎病毒超变量区域1 基因序列分析交叉反应性嵌合体抗原

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