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Physarum polycephalum-inspired adaptive optimization design of artificial microtubular networks

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Science China Chemistry 2025年

作者： Si-Min Zeng Di-Wei zheng Ting Pan Xing-Lan Ding yun Zhang Chi-Hui Yang Si-Xue Cheng Xian-zheng Zhang Key Laboratory of Biomedical Polymers of Ministry of Education&Department of Chemistry Wuhan University

Natural biological microtubular networks have undergone adaptive evolutionary selection and may offer viable solutions to design challenges in artificial microtubular networks. The plasmodium of the slime mold Physarum polycephalum(P. polycephalum) extends continuously to form a protoplasmic microtubular network structure, directly connecting food *** simulations revealed that the formation of this adaptive P. polycephalum microtubular network could be captured by a mathematical algorithm. Inspired by the P. polycephalum microtubular networks, we propose an adaptive optimization design method for artificial microtubular networks. Specifically, we utilized hydrogels with biodegradable and tissue-adhesive properties to replicate the P. polycephalum microtubular networks via photomask. In Rhodamine B diffusion and glucosecatalyzed reaction experiments, we found that the P. polycephalum microtubular networks exhibited significantly enhanced efficiency compared to vascular and artificial networks. Furthermore, we demonstrated the potential for uric acid(UA) degradation of the hydrogels with a real P. polycephalum microtubular network loaded with urate oxidase(UOx) in a rodent model of hyperuricemia. And this network achieved more than double the effect of the artificial network. This underscores the potential of natural microtubular networks to replace artificial microtubular networks.

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基于耦合界面键合效应的石墨烯磨损研究

原子与分子物理学报 2025年第6期42卷 66-75页

作者：郑云飞卢艳武汉科技大学冶金装备及其控制教育部重点实验室武汉430081 武汉科技大学机械传动与制造工程湖北省重点实验室武汉430081 武汉科技大学精密制造研究院武汉430081

石墨烯作为二维固体润滑材料,其超滑特性不仅是物理作用结果,其化学键结构机制下的摩擦化学现象,是深入理解石墨烯摩擦性能的关键.本文采用分子动力学(MD)方法构建了多重层数石墨烯增强不同粗糙形貌的金属基底模型,实现了其与金刚石尖... 详细信息

石墨烯作为二维固体润滑材料,其超滑特性不仅是物理作用结果,其化学键结构机制下的摩擦化学现象,是深入理解石墨烯摩擦性能的关键.本文采用分子动力学(MD)方法构建了多重层数石墨烯增强不同粗糙形貌的金属基底模型,实现了其与金刚石尖端滑动过程的动态分析,揭示了考虑尖端与石墨烯之间存在界面键时石墨烯层的理化耦合作用下的磨损机理.研究结果表明:当考虑金刚石尖端与石墨烯之间化学键合时,石墨烯发生磨损破裂的临界载荷相对于不考虑界面化学键时的值减小,这是由于界面键的形成会剥离石墨烯导致石墨烯断裂所致;金属基底的粗糙度也是决定石墨烯发生磨损破裂时临界载荷的重要因素之一,当粗糙度增大,临界载荷减小,同时通过增加石墨烯层的层数(增韧)来提高石墨烯发生磨损破裂失效的临界载荷.

关键词：石墨烯层界面键分子动力学磨损破裂

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The second Eshelby problem and its solvability

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Acta Mechanica Sinica 2012年第5期28卷 1331-1333页

作者： Wen-Nan Zou Quan-shui zheng Institute for Advanced Study Nanchang University Department of Engineering Mechanics Tsinghua University

It is still a challenge to clarify the dependence of overall elastic properties of heterogeneous materials on the microstructures of non-elliposodal inhomogeneities （cracks, pores, foreign particles）. From the theory of elasticity, the formulation of the perturbance elastic fields, coming from a non-ellipsoidal inhomogeneity embedded in an infinitely extended material with remote constant loading, inevitably involve one or more integral equations. Up to now, due to the mathematical difficulty, there is almost no explicit analytical solution obtained except for the ellipsoidal inhomo- geneity. In this paper, we point out the impossibility to trans- form this inhomogeneity problem into a conventional Eshelby problem by the equivalent inclusion method even if the eigenstrain is chosen to be non-uniform. We also build up an equivalent model, called the second Eshelby problem, to investigate the perturbance stress. It is probably a better template to make use of the profound methods and results of conventional Eshelby problems of non-ellipsoidal inclusions.

关键词： The second Eshelby's problem Linear elasticity Non-ellipsoidal inhomogeneity Overall elastic proper-ties

Experimental study of drag reduction characteristics related to the multifactor coupling of a bionic jet surface

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Journal of Hydrodynamics 2019年第1期31卷 186-194页

作者： yun-qing Gu Song-wei Yu Jie-gang Mou Tian-xing Fan shui-hua zheng Gang Zhao College of Mechanical Engineering Zhejiang University of TechnologyHangzhou 310014China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

To study the drag reduction of a jet surface,an experiment is conducted with a gyrorotor *** aim of this study is to analyze the influence of the jet aperture,the jet angle and the rotational velocity coupled with the jet velocity on the friction torque acting on a jet surface model by using a jet surface drag reduction testing experimental *** drag reduction characteristics of the jet surface are also *** results show that the maximum drag reduction rate is attained when the jet diameter is 5 mm and the jet velocity is 1.2 m/*** influence of the jet velocity on the drag reduction rate decreases as the diameter ***,the maximum drag reduction rate can be attained when the angle of the jet is 30° and the velocity of the jet is 1.0 m/*** the jet diameter is small,the influence of the jet velocity on the drag reduction rate is small,whereas the maximum drag reduction rate is attained when the jet angle is 30° and the jet velocity is 1.0 m/*** the jet angle is 15°,the drag reduction rate fluctuation is *** maximum drag reduction rate is attained when the rotational velocity is 2 100 r/min and the jet velocity is 1.0 m/*** results show that the best scheme is A2B2D3 A maximum drag reduction rate of 8.57% can be *** effective control of the jet effect on the separation of the boundary layer demonstrates the drag reduction principle of a bionic jet surface.

关键词： Drag reduction bionic jet surface friction torque coupling experiment

Rate-dependent constitutive model of poly(ethylene terephthalate) for dynamic analysis

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2010年第10期11卷 811-816页

作者： Qiang LI Shu-lian LIU shui-ying zheng Institute of Chemical Machinery Zhejiang University Hangzhou 310027 China Department of Electro-Mechanical Engineering Zhejiang University of Science and Technology Hangzhou 310023 China

Uniaxial tensile testing at strain rates ranging from 10-3 to 10-1 s-1 was carried out to study the rate-dependent me-chanical behavior for poly(ethylene terephthalate) (PET) used in the packaging industry. The experimental results show that a rate-dependent plastic behavior exists for PET material. The value of the yield strength was found to increase with the increasing strain rate. A new constitutive model based on the improved Cowper-Symonds rate-dependent constitutive model is proposed to describe the mechanical behavior of PET material in the strain rate ranging from 10-3 to 10-1 s-1, providing more accurate material data for the subsequent simulation analysis of drop test and dynamic buckling. The predictions obtained using the proposed model are compared with experimental results of the improved Cowper-Symonds model. The simulating results of the proposed model agree well with the experimental data. For a low strain rate, the predictions of this model are more precise than those obtained using the improved Cowper-Symonds model. This confirms that the new constitutive model is suitable for describing the me-chanical behavior of PET material at a low strain rate and modeling impact problem.

关键词： Rate-dependent Tensile testing Constitutive model Strain rate Poly(ethylene terephthalate) (PET)

Characteristics and mechanism investigation on drag reduction of oblique riblets

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Journal of Central South University 2017年第6期24卷 1379-1386页

作者： GU yun-qing FAN Tian-xing MOU Jie-gang WU Deng-hao zheng shui-hua College of Mechanical and Engineering Zhejiang University of TechnologyHangzhou 310014China Zhijiang College Zhejiang University of TechnologyHangzhou 310024China Institute National Polytechnique of Grenoble Joseph Fourier UniversityGrenoble 38031France

This work primarily focuses on the drag reduction characteristics and mechanism investigation of oblique riblets. First, a calculation model of the oblique riblets surface is established, and Reynolds stress model(RSM) turbulence model is used for numerical simulation of the oblique riblets flow field. Subsequently, the influence of inclination angle between flow direction and arrangement direction of riblets on friction resistance and drag reduction rate is further analyzed. Through the investigation of the distribution of shear stress, pressure stress and velocity in oblique riblets boundary layer, the oblique riblets drag reduction mechanism is finally revealed. Results show that, with increase of velocity and inclination angle, the pressure resistance increases obviously, along with the decreasing of the viscous resistance distinctly. The maximum drag reduction rate of the oblique riblets is 7.33%. Moreover, when the inclination angle increases, the wall shear stress reduces on oblique riblets surface; while differential pressure increases at both sides of oblique riblets tips. In addition, when inclination angle is small, the secondary vortex at oblique riblets tips will disappear soon. New vortices will be formed inside the oblique riblets and cause the decrease of viscosity resistance. Thus, oblique riblets show a better drag reduction effect and have an effective control on boundary layer.

关键词： oblique riblets drag reduction Reynolds stress model (RSM) secondary vortex numerical simulation

羟基磷灰石改性竹笋壳生物炭的合成及吸附性能研究

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分析测试学报 2025年第1期44卷 126-134页

作者：夏蒸雷兰石铁应鲍云云梁汝萍邱建丁东华理工大学核资源与环境国家重点实验室江西南昌330013 南昌大学化学化工学院江西南昌330031

该研究以竹笋壳为原料合成了具有多孔结构和亲水性磷酸基团的羟基磷灰石改性竹笋壳生物炭(BSHAP),用于高效吸附废水中的铀酰离子(UO_(2)^(2+))。BS-HAP的多孔结构可有效增加与UO_(2)^(2+)的接触面积,促进对UO_(2)^(2+)的吸附;BS-HAP中... 详细信息

该研究以竹笋壳为原料合成了具有多孔结构和亲水性磷酸基团的羟基磷灰石改性竹笋壳生物炭(BSHAP),用于高效吸附废水中的铀酰离子(UO_(2)^(2+))。BS-HAP的多孔结构可有效增加与UO_(2)^(2+)的接触面积,促进对UO_(2)^(2+)的吸附;BS-HAP中的磷酸基团可为化学吸附UO_(2)^(2+)提供结合位点,使得BS-HAP对UO_(2)^(2+)具有优异的吸附性能。同时,Ca^(2+)与UO_(2)^(2+)之间的离子交换作用以及生物炭与UO_(2)^(2+)之间的静电相互作用,协同促进了BSHAP对UO_(2)^(2+)的吸附。在酸性条件下,BS-HAP对UO_(2)^(2+)的吸附容量为815.2 mg·g^(-1)。BS-HAP不仅对UO_(2)^(2+)具有强的吸附能力,还具有良好的选择性和稳定性,即使经多次循环使用,仍能保持对UO_(2)^(2+)的高效去除能力。BS-HAP为含铀废水处理提供了有效方法,对推动绿色可持续的废水处理技术发展具有重要意义。

关键词：竹笋壳生物炭羟基磷灰石铀酰离子吸附

基于语音信号时频特征融合的帕金森病检测方法

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郑州大学学报（理学版） 2025年第1期57卷 53-60页

作者：王晨哲季薇郑慧芬李云南京邮电大学计算机学院江苏南京210023 南京邮电大学通信与信息工程学院江苏南京210003 南京医科大学附属老年医院江苏南京210009

发音障碍是帕金森病的早期症状之一。近年来,基于语音信号的帕金森病检测的研究大多采用梅尔刻度下的相关语音特征与深度神经网络模型相结合的方法。然而,现有的模型无法充分关注语音信号的全局时序信息,且梅尔刻度特征在准确表征帕金... 详细信息

发音障碍是帕金森病的早期症状之一。近年来,基于语音信号的帕金森病检测的研究大多采用梅尔刻度下的相关语音特征与深度神经网络模型相结合的方法。然而,现有的模型无法充分关注语音信号的全局时序信息,且梅尔刻度特征在准确表征帕金森病的病理信息方面效果有限。为此,提出了一种基于语音时频特征融合的帕金森病检测方法。首先,提取语音的梅尔频率倒谱系数,并将其作为模型的输入。接着,在已有的S-vectors模型中引入Conformer编码器模块,以提取语音的时域全局特征。最后,将与帕金森病语音检测相关的频域全局特征嵌入时域特征中进行时频信息融合,以实现帕金森病语音检测。在公开帕金森病语音数据集和自采语音数据集上验证了方法的有效性。

关键词：帕金森病梅尔频率倒谱系数 S-vectors Conformer 时频特征融合

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Decay of the 2D Periodic Stationary Viscous Surface Waves

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Acta Mathematica Sinica,English Series 2018年第12期34卷 1837-1862页

作者： yun Rui zheng School of Mathematical Sciences Qufu Normal University

We consider the evolution of viscous fluids in a 2D horizontally periodic slab bounded above by a free top surface and below by a fixed fiat bottom. This is a free boundary problem. The dynamics of the fluid are governed by the incompressible stationary Navier-Stokes equations under the influence of gravity and the effect of surface tension. We develop the global theory of solutions in low regularity Sobolev spaces for small data by nonlinear energy estimates.

关键词： Free boundary problems global existence Navier Stokes equations