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基于RHT本构模型的连续装药预裂爆破孔距优化研究

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高压物理学报 2025年第1期39卷 109-118页

作者：张伟王建国王勉陶家龙昆明理工大学国土资源工程学院云南昆明650093 云南省教育厅爆破新技术工程研究中心云南昆明650093

为解决北衙金矿在使用预裂爆破技术时整体爆破效果不佳的问题,基于RHT损伤本构模型,利用ANSYS/LS-DYNA数值模拟软件,开展了不同孔距下预裂爆破的数值模拟研究。结果表明:当预裂孔炮孔间距为120 cm时,孔间裂纹存在较为明显的分叉,且裂纹... 详细信息

为解决北衙金矿在使用预裂爆破技术时整体爆破效果不佳的问题,基于RHT损伤本构模型,利用ANSYS/LS-DYNA数值模拟软件,开展了不同孔距下预裂爆破的数值模拟研究。结果表明:当预裂孔炮孔间距为120 cm时,孔间裂纹存在较为明显的分叉,且裂纹扩展范围较大;当炮孔间距为130 cm时,裂纹向四周扩展的范围减小,且炮孔周围岩石的损伤程度明显降低;当炮孔间距增加至140 cm时,相邻预裂孔连线上的裂纹仅在局部连通,无法实现孔间贯穿。上述结果说明,130 cm的炮孔间距在降低预裂爆破自身对岩体的扰动与实现有效爆破成缝之间达到了平衡。基于数值模拟试验结果开展了现场试验,爆破效果良好。研究结果可为矿山的预裂爆破设计和施工提供参考。

关键词：预裂爆破连续装药孔距优化 RHT本构模型

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A Spectral Element Method to Compute Earth’s Free Core Nutation

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Research in Astronomy and Astrophysics 2023年第9期23卷 171-179页

作者： mian zhang Cheng-Li Huang CAS Key Laboratory of Planetary Sciences Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China

The Free Core Nutation(FCN)is a rotational mode caused by non-alignment of the rotation axis of the core and of the *** period observed by VLBI and superconducting gravimetry is around 430 sidereal days(Sd)with precision of better than 1 Sd,while its“theoretical”period calculated by traditional approaches and a given Earth model ranges from 450 to 470 *** gap of about 30 Sd is significant compared with its observation *** propose a spectral element method to compute the period of FCN and obtain a period of 434 Sd which is very close to the observed value.

关键词： Earth-planets and satellites interiors-methods numerical

A Linear Operator Method to Compute the Normal Modes with Rotation of any Asymmetric 3D Planet with Pure Vector Spherical Harmonics

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Research in Astronomy and Astrophysics 2023年第10期23卷 224-254页

In order to compute the free core nutation of the terrestrial planets, such as Earth and Mars, the Moon and lower degree normal modes of the Jovian planets, we propose a linear operator method(LOM). Generalized surface spherical harmonics(GSSHs) are usually applied to the elliptical models with a stress tensor, which cannot be expressed in vector spherical harmonics explicitly. However, GSSHs involve complicated math. LOM is an alternative to GSSHs,whereas it only deals with the coupling fields of the same azimuthal order m, as is the case when a planet model is axially symmetric and rotates about that symmetry axis. We extend LOM to any asymmetric 3D model. The lower degree spheroidal modes of the Earth are computed to validate our method, and the results agree very well with what is observed. We also compute the normal modes of a two-layer Saturn model as a simple application.

关键词： planets and satellites:interiors Earth planets and satellites:gaseous planets

Microbial self-healing of cracks in cement-based materials and its influencing factors

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Frontiers of Structural and Civil Engineering 2023年第11期17卷 1630-1642页

作者： Xiaoniu YU Qiyong zhang Xuan zhang mian LUO Jiangsu Key Laboratory of Construction Materials Southeast UniversityNanjing 211189China College of Engineering and Technology Southwest UniversityChongqing 400715China School of Civil Engineering and Architecture Jiangsu University of Science and TechnologyZhenjiang 212114China College of Civil Science and Engineering Yangzhou UniversityYangzhou 225127China

Cement-based materials are brittle and crack easily under natural *** can reduce service life because the transport of harmful substances can cause corrosion damage to the *** review discusses the feasibility of using microbial self-healing agents for crack *** and spherical carriers can be used to load microbial self-healing agents and protect microbes,which prolongs the self-healing *** area self-healing ratio,permeability,mechanical strength,precipitation depth method,numerical modeling,and ultrasonic method can be employed to identify the self-healing effect of ***,the self-healing mechanism is systematically *** results showed that microbial self-healing agents can repair cracks in cement-based materials in underground projects and dam *** difficulties and future development of self-healing cracks were analyzed.A microbial selfhealing agent was embedded in the cement-based material,which automatically repaired the developing *** the development of intelligent building materials,self-healing cracks have become the focus of attention.

关键词： cement-based materials cracks microbial self-healing agent mechanism intelligent building materials

Mechanokinetics of receptor-ligand interactions in cell adhesion

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Acta Mechanica Sinica 2015年第2期31卷 248-258页

作者： Ning Li Shouqin Lü Yan zhang mian Long Key Laboratory of Microgravity(National Microgravity Laboratory) Center of Biomechanics and Bioengineeringand Beijing Key Laboratory of Engineered Construction and MechanobiologyInstitute of MechanicsChinese Academy of Sciences

Receptor-ligand interactions in blood flow are crucial to initiate such biological processes as inflammatory cascade,platelet thrombosis,as well as tumor *** mediate cell adhesion,the interacting receptors and ligands must be anchored onto two apposing surfaces of two cells or a cell and a substratum,i.e.,two-dimensional（2D）binding,which is different from the binding of a soluble ligand in fluid phase to a receptor,i.e.,three-dimensional（3D） *** numerous works have been focused on3 D kinetics of receptor-ligand interactions in the immune system,2D kinetics and its regulations have been less understood,since no theoretical framework or experimental assays were established until *** only does the molecular structure dominate 2D binding kinetics,but the shear force in blood flow also regulates cell adhesion mediated by interacting receptors and ***,we provide an overview of current progress in 2D binding and regulations,mainly from our *** issues of theoretical frameworks,experimental measurements,kinetic rates and binding affinities,and force regulations are discussed.

关键词： Receptor-ligand interactions Selectins β_2 integrins 2D binding kinetics

Tribocorrosion behavior of antibacterial Ti-Cu sintered alloys in simulated biological environments

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Rare Metals 2022年第6期41卷 1921-1932页

作者： Jia-Qi zhang Shuang Cao Ying Liu mian-mian Bao Jing Ren Sheng-Yi Li Er-Lin zhang Jian-Jie Wang Departments of Immunology College of Basic MedicineJiamusi UniversityJiamusi 154007China Key Laboratory for Anisotropy and Texture of Materials School of Materials Science and EngineeringEducation Ministry of ChinaNortheastern UniversityShenyang 110819China Research Center for Metallic Wires Northeastern UniversityShenyang 110819China

Ti-Cu alloys have strong antibacterial proper-ties,high strength and excellent corrosion resistance,which might be used in orthopedic and dental *** this paper,the tribocorrosion behaviors of Ti-Cu alloy with different Cu contents were investigated in four simulated biological environments compared with *** results showed that Ti-Cu sintered alloy exhibited higher corro-sion resistance,lower coefficient friction and wear loss than cp-Ti in all tested solutions due to the formation of fine and homogeneously distributed Ti_(2)Cu phase,espe-cially in solution with lower F ion and *** Cu content and extrusion process improved the corrosion resistance and the wear resistance because of high Ti_(2)Cu phase fraction and fine grain ***,aggressive solution,such as the solution with lower F ion and pH,accelerated wear in comparison with other solutions for cp-Ti and Ti-Cu sintered *** electron microscope(SEM)surface morphology demonstrated that the wear mecha-nism of cp-Ti during tribocorrosion process was mainly abrasive wear and adhesive wear while that of Ti-Cu alloy was abrasive *** summary,Ti-Cu sintered alloys showed much better tribocorrosion property than cp-Ti,which shows great potential application in condition for wear and corrosion resistance.

关键词： Ti-Cu alloys Tribocorrosion Corrosion Wear In vitro Antibacterial metal alloy

Influence of Megaregolith on the Thermal Evolution of Mercury's Silicate Shell

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Research in Astronomy and Astrophysics 2022年第3期22卷 271-284页

作者： Jing-Chun Xie mian zhang Cheng-Li Huang Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China CAS Key Laboratory of Planetary Sciences Shanghai Astronomical ObservatoryChinese Academy of SciencesShanghai 200030China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China

A so-called megaregolith layer that is considered to be produced by continuous impacts in Mercury’s early stages is integrated into the thermal evolution models of Mercury to study its influence on the thermal evolution of Mercury’s silicate *** research first implements a one-dimensional parametric global thermal evolution *** results indicate that megaregolith directly affects the thermal evolution of Mercury’s silicate shell by virtue of its good insulation *** way megaregolith exerts its influence is by prolonging the process of partial melting and reducing the heat loss,resulting in a thicker crust and thinner stagnant *** for the deep parts of the silicate shell,it is suggested that more energy is taken away from the mantle due to the longer partial melting,leading to lower temperatures below the crust compared with the case in the absence of megaregolith,which further helps to advance the formation time of the inner core and promote its final *** addition,we also carry out a simplified two-dimensional mantle convection simulation as a supplement to the one-dimensional *** two-dimensional simulation depicts a typical mantle plume fractional melting *** calculations indicate that megaregolith may be key to the long-term volcanic activities on *** far as the megaregolith itself is concerned,the thermal structure of this particular layer is more sensitive to thermal conductivity,suggesting that for such a highly fragmented structure,the thermal conductivity coefficient plays a key role in its *** work emphasizes the importance of megaregolith to the evolution of Mercury.

关键词： planets and satellites:terrestrial planets planets and satellites:physical evolution planets and satellites:interiors

An integrated analysis of mRNA-miRNA transcriptome data revealed hub regulatory networks in three genitourinary cancers

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BIOCELL 2017年第1期41卷 19-26页

作者： mian LIU Xumeng zhang Center for Reproductive Medicine Department of Obstetrics and GynecologyNanfang HospitalSouthern Medical UniversityGuangzhou 510515P.R.C State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen UniversityGuangzhou 510006P.R.C

Bladder,kidney,prostate and testicular carcinoma are the top four genitourinary cancers in *** we analyzed mRNA and miRNA expression profiles of carcinomas of the bladder(TCC),kidney(ccRCC)and testis(TGCT)to uncover their specific regulatory *** gene expression profiles of GSE31617 were downloaded from GEO database,which contained 27 samples,including 10 TCC,7 TGCT and 10 *** up-and downregulated differentially expressed genes(DEGs)and differentially expressed microRNAs(DEmiRNAs)of each cancer were selected and target genes of DEmiRNAs were *** interaction network of the shared genes and target genes of DEmiRNAs of each cancer was predicted by STRING and constructed by *** each cancer,we build regulatory networks of hub genes selected and conducted GO analysis of enriched ***,we chose four hub genes(SALL4,RHEB,CDC42 and TNN)for survival analysis in OncoLnc database,and they all had effects on the survival rate of another genitourinary cancer-kidney renal clear cell carcinoma(KIRC).In conclusion,the present study indicated that the identified hub genes promote our understanding of molecular mechanisms underlying the development of three genitourinary cancers,and might be used as molecular targets and diagnostic biomarkers for the treatment of them.

关键词： Genitourinary cancers Differentially expressed genes Differentially expressed miRNAs Hub genes

Deformation Mechanisms and Safe Drilling Fluids Density in Extremely Thick Salt Formations

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Petroleum Science 2007年第4期4卷 56-61页

作者： Yang Henglin Chen mian zhang Guangqing Drilling Research Institute CNPC Beijing 100097 China School of Petroleum Engineering China University of Petroleum Beijing 102249 China

Hydrocarbons are very often associated with salt structures. The oil and gas industry is often required to drill along and through long salt sections to reach and recover hydrocarbons. The unique physical properties of salt require special techniques to ensure borehole stability and adequate casing design. This paper assumed that the mechanical behavior of salt is regulated by the magnitude of mean stress and octahedral shear stress and under the influence of different stress conditions the deformation of rock salt can be represented by three domains, i.e. compression domain, volume unchanged domain, and dilatancy domain, which are separated by a stress dependent boundary. In the compression domain, the volume of salt decreases until all microcracks are closed, with only elastic deformation and pure creep; in the volume unchanged domain the deformation is considered steady incompressible flow controlled by pure creep; and in the dilatancy domain the volume of salt increases during deformation due to micro-cracking, causing damage and accelerating ＂creep＂ until failure. This paper presents a hypothesis that the borehole is stable only when the magnitude of octahedral shear stress is below the dilatancy boundary. It gives the design method for determining drilling fluids density, and calculates the closure rate ofborehole with the recommended drilling fluids density. If the closure rate of the borehole is less than 0.1%, the drilling fluids density window can be used during drilling through extremely thick salt formations.

关键词： Rock salt borehole stability deformation mechanisms constitutive equations equivalent viscosity drilling fluids density