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Numerical investigation of the interactions between a laser-generated bubble and a particle near a solid wall

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Journal of Hydrodynamics 2021年第2期33卷 311-322页

作者： jian-yong Yin yong-xue Zhang jian-jun Zhu Liang Lü Shi-da Li College of Mechanical and Transportation Engineering China University of Petroleum-BeijingBeijing 102249China Beijing Key Laboratory of Process Fluid Filtration and Separation China University of Petroleum-BeijingBeijing 102249China School of International Education Hainan Medical UniversityHaikou 571199China Department of Thermal Engineering Chengde Petroleum CollegeChengde 067000China

The interactions between the bubbles and the particles near structures are important issues for the applications of the cavitation in the fluid *** study the hidden microscopic mechanisms,a numerical method for simulating the laser-generated bubble between the solid wall and a particle is developed in this paper with considerations of the viscosities and the compressibility of the gas and the liquid phases,as well as the surface tension between *** gas-liquid interface is tracked by the coupling level set and the volume of fluid(CLSVOF)*** numerical results clearly reveal that the particle can influence the cavitation bubble *** potential damage of the nearby structures is numerically quantified in terms of the wall pressure,which helps better understand the synergetic effects of the particle on the *** effects of three dimensionless parameters on the wall pressure are also investigated,especially,on the peak pressure,namely,γ1(defined as L_(1)/R_(max),where L_(1)is the distance from the center of the initial bubble to the solid wall and R_(max)is the maximum bubble radius),γ_(2)(defined as L_(2)/R_(max),where L_(2)is the distance from the lower surface of the spherical particle to the initial bubble center)andθ(defined as Rp/R_(max),where Rp is the spherical particle radius).Further numerical results show that these parameters play a dominant role in determining the peak *** y_(1)mainly resulted from the liquid ***γ1>1.00,the peak pressure is caused by the shock *** the increase ofθor decrease ofγ_(2),the peak pressure ***γ_(2)>2.00,the effect of the particle on the bubble behavior can be neglected.

关键词： Cavitation bubble spherical particle coupling level set and the volume of fluid(CLSVOF) solid wall OpenFOAM

Sequence-Controlled Synthesis of Alternating Poly(ester amide)s using Water as Control Agent in One-Pot

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Chinese Journal of Polymer Science 2024年第8期42卷 1015-1020页

作者： Tao Liu Fang-Fang Niu Kan Cheng Yu-Min Xia Bo-Mou ma Xue-Li Wang jian-yong Yu yong He State Key Laboratory for Modification of Chemical Fibers and Polymer materials College of Materials Science and EngineeringDonghua UniversityShanghai 201620China Innovation Center for Textile Science and Technology Donghua UniversityShanghai 201620China

Poly(ester amide)s(PEAs)attract much attention as a new kind of biodegradable ***,the synthesis of PEAs with sequence-regulated chain structures is still complicated due to the multistep polymerization,high monomer purity,as well as the usage of organic solvents,which greatly inhibits its development and ***,a one-pot strategy without solvent was developed to synthesize the alternating PEA fromα,ω-amino alcohol and dicarboxylic acid by sequential polycondensation,where water was used as the controlling agent for amidation and ***,the amidation and esterification were controlled to proceed in turn by adding or removing water,realizing the one-pot preparation of alternating *** resultant PEA is characterized by^1H-and^(13)C-NMR,and its chain structure is confirmed to be highly quasi-alternating similar to alternating PEAs prepared by classical methods The evaluations from DSC and Dma demonstrate that the properties of quasi-alternating PEA(T_(m)=102℃,ΔH_(m)=30J·g^(-1))are far superior to those of random PEA(T_(m)=72℃,ΔH_(m)<1 J·g^(-1)).

关键词： Biodegradable macromolecules Polymer architectures Sequence-controlled synthesis One-pot polymerization

Compensate Effect Under Time-Scale Transformation in Vaidya-Bonner Space-Time

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Chinese Physics Letters 1996年第7期13卷 492-495页

作者： ma yong ZHAO Zheng Department of Physics Chongqing Teachers CollegeChongqing 630047 Department of Physics Beijing Normal UniversityBeijing 100875

The Hawking effect in the Vaidya-Bonner space-time can be considered as a compensate effect of the scale transformation of coordinate *** gauge potential is the contraction of the affine *** is found that the rate of change of temperature can be obtained as the pure gauge potential of the compensate field,in addition to the Hawking temperature which was known from the stationary black holes.

关键词： gauge Transformation Vaidya

A new construction for the statistical theory of the nonextensive systems

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Chinese Science Bulletin 2014年第21期59卷 2528-2533页

作者： Hui-Yi Tang Tie-Ling Song jian-Hui Wang yong-Li ma State Key Laboratory of Surface Physics and Department of Physics Fudan University Department of Physics Nanchang University

We propose a new statistical theory for classical and quantum small *** is a generalized scheme of the Boltzmann–Gibbs statistical theory by extending the Boltzmann–Gibbs statistical factor from infinite systems to finite systems based on the microcanonical ensemble distribution function and keeping this factor in all thermodynamic *** reconstruct the statistical theory for finite systems by obtaining the expression of the average particle number and the thermodynamic quantities such as entropy and specific heat,in the finite *** also explore the discontinuous phase transitions in the interacting classical nanoscale gases without the thermodynamic limit.

关键词：统计理论函数系统有限系统热力学极限量子体系玻耳兹曼热力过程热力学量

复式钢管混凝土墩柱轴压性能及承载力提高分析

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New Active Organic Substance in Oyster Shell Capable of Scavenging Oxygen Free Radicals with High Efficiency

工程力学 2025年第1期42卷 209-222页

作者：张玉芬郝圣旺李栋磊方永坚燕山大学建筑工程与力学学院秦皇岛066099 河北工业大学土木与交通学院天津300401 河北省土木工程绿色建造与智能运维重点实验室秦皇岛066099

为提升矩形钢管混凝土独柱墩的工作性能，在其截面内套异心双圆钢管形成新型复式钢管混凝土墩柱。该文进行了7个墩柱轴压荷载试验，通过对比空钢管柱、矩形墩柱和夹层墩柱分析了新型墩柱的破坏形态、钢管应变发展及承载力和延性差异，... 详细信息

为提升矩形钢管混凝土独柱墩的工作性能，在其截面内套异心双圆钢管形成新型复式钢管混凝土墩柱。该文进行了7个墩柱轴压荷载试验，通过对比空钢管柱、矩形墩柱和夹层墩柱分析了新型墩柱的破坏形态、钢管应变发展及承载力和延性差异，最后利用钢管和混凝土的组合效应原理进行组合墩柱轴压承载力提高分析。研究得出新型复式钢管混凝土墩柱轴压破坏形态为鼓曲破坏，其极限承载力较夹层墩柱提高20%，较矩形墩柱提高22%，延性提高效果更为明显;新型墩柱内、外钢管应变发展充分，说明钢管较好地发挥了竖向承载和横向约束混凝土的能力;根据钢板的正则化宽厚比和屈曲后强度计算得出，内、外钢管在混凝土的支撑下承载力提高15%，混凝土在钢管的约束下承载力提高49%;根据约束组合效应得出，新型墩柱整体承载力提高31%;采用等效套箍系数计算的新型墩柱承载力与试验值绝对误差在4%以内，说明新型复式钢管混凝土墩柱符合钢管混凝土统一理论。研究结果表明，新型复式钢管混凝土墩柱在约束混凝土效应方面明显提高，构件的承载力较高、延性较好，具有较强的工程应用前景。

关键词：新型复式钢管混凝土墩柱轴压性能破坏形态承载力套箍系数

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Chemical Research in Chinese Universities 2008年第2期24卷 171-174页

作者： ma jian-hua College of Biology Engineering Jimei University Xiamen 361021 P. R. China

A light purple organic active substance capable of scavenging hydroxyl radical（OH） with a high efficiency was extracted from Oyster shell at an extraction rate of 2.49%. It was found for the first time that this active substance may scavenge OH with the efficiency far higher than that of vitamin C. This active substance may scavenge also superoxide radical（O2） although the scavenging efficiency is far lower than that of vitamin C. Infrared spectrometry and routine chemical analysis primarily reveal that this active substance belongs to glycoprotein.

关键词： Oyster shell Glycoprotein Scavenging Hydroxyl radical Superoxide radical

A high-order scheme based on lattice Boltzmann flux solver for viscous compressible flow simulations

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Applied mathematics and Mechanics(English Edition) 2022年第10期43卷 1601-1614页

作者： jian QIN Jie WU Chao ma State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China Key Laboratory of Unsteady Aerodynamics and Flow Control Ministry of Industry and Information TechnologyNanjing University of Aeronautics and AstronauticsNanjing210016China Department of Aerodynamics Nanjing University of Aeronautics and AstronauticsNanjing210016China

In this paper,a high-order scheme based on the lattice Boltzmann flux solver(LBFS)is proposed to simulate viscous compressible *** flux reconstruction(FR)approach is adopted to implement the spatial *** LBFS is employed to compute the inviscid flux by using the local reconstruction of the lattice Boltzmann equation solutions from macroscopic flow ***,a switch function is used in LBFS to adjust the magnitude of the numerical ***,it is more beneficial to capture both strong shock waves and thin boundary ***,the viscous flux is computed according to the local discontinuous Galerkin *** typical compressible viscous problems,including manufactured solution case,lid-driven cavity flow,supersonic flow around a cylinder and subsonic flow over a NACA0012 airfoil,are simulated to demonstrate the accuracy and robustness of the proposed FR-LBFS.

关键词： high-order method flux reconstruction lattice Boltzmann flux solver(LBFS) viscous compressible flow

Sintering behavior and thermal conductivity of Y_(2)O_(3) fully stabilized HfO_(2) ceramics

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Rare Metals 2021年第5期40卷 1255-1266页

作者： Chun Li jian He Yue ma School of materials Science and Engineering Beihang UniversityBeijing 100191China School of Energy and Power Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural materials and Coatings Technology(Ministry of Industry and Information Technology) Beihang UniversityBeijing 100191China

A series of Y_(2)O_(3) fully stabilized HfO2 ceramics(Hf_(1-x)Y_(x)O_(2-0.5x),x=0.20,0.24,0.28,0.32,0.36 and 0.40)were synthesized by solid-state reaction at 1500℃.The phase composition,thermal conductivity and sintering behavior at 1400℃ of the ceramic bulks were *** Hf_(1-x)Y_(x)O_(2-0.5x) ceramics were comprised of pure cubic phase with disordered fluorite *** phase transformation occurred in the ceramics with Y3+doping concentration ranging from 0.24 to *** Hf_(0.64)Y_(0.36)O_(1.82) and Hf_(0.6)Y_(0.4)O_(1.8) samples revealed the lowest grain growth rate when sintered at 1400℃,indicating good resistance to ***,the Vicker’s hardness and Young’s modulus after annealed for 96 h at 1400℃ for the Hf_(0.64)Y_(0.36)O_(1.82) sample were 8.97 and 200 GPa,respectively,much lower than those of the Hf_(0.6)Y_(0.4)O_(1.8)(14.51 and 237 GPa,respectively).The thermal conductivity of Hf_(1-x)Y_(x)O_(2-0.5x) first decreased and then increased slowly as the Y3+content increased,and the associated mechanism was discussed.

关键词： Yttria fully stabilized hafnia Sintering Mechanical properties Thermal conductivity

Recent progress on dense nuclear matter in skyrmion approaches

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Science China(Physics,Mechanics & Astronomy) 2017年第3期60卷 1-24页

作者： yong Liang ma mannque Rho Center of Theoretical Physics and College of Physics Jilin University Institut de Physique Th'eorique CEA Saclay

The Skyrme model provides a novel unified approach to nuclear physics. In this approach, single baryon, baryonic matter and medium-modified hadron properties are treated on the same footing. Intrinsic density dependence(IDD) reflecting the change of vacuum by compressed baryonic matter figures naturally in the approach. In this article, we review the recent progress on accessing dense nuclear matter by putting baryons treated as solitons, namely, skyrmions, on crystal lattice with accents on the implications in compact stars.

关键词： Skyrme model hidden symmetries skyrmion crystal holographic nucleon BPS nuclei compact stars