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Depinning Dynamics of Two-Dimensional Charged Colloids on a Random Laser-Optical Substrate

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Communications in Theoretical Physics 2009年第5期51卷 938-940页

作者： cao yi-gang WANG Hong-Ling YANG gang HAN Hong-Pei School of Physics and Engineering Zhengzhou University Zhengzhou 450001 China Information College of Electronic-Engineering Xuchang University Xuchang 310018 China

Using Langevin simulations, we. investigate the depinning dynamics of two-dimensional charged colloids on a random laser-optical substrate. With an increase in the strength of the substrate, we find a transition from crystal to smectic flows above the depinning. A power-law scaling relationship between average velocity and applied driving force could be obtained for both flows, and we find that the scaling exponents are no bigger than 1 for the crystal and are bigger than 1 for the smectic flows.

关键词： charged colloids laser-optical substrate depinning

Numerical Study on the Two-Dimensional Vortex System with Random Pinning

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Chinese Physics Letters 1999年第9期16卷 689-691页

作者： cao yi-gang YU Ya-bin JIAO Zheng-kuan Department of Physics Zhejiang UniversityHangzhou 310027

We study numerically the dynamic behavior of the two-dimensional vortex lattice, moving in a random pinning potential under the action of an external driving force. Different densities of randomly distributed pointlike pinning centers and different vortex-vortex interacting strength are considered. Then the elastic and plastic regimes are found to be dependent on the relation between the vortex-vortex and the vortex-pin interacting potentials. The critical driving force increases with increasing density of pinning centers and with decreasing of the vortex-vortex interacting strength. The simulated results are consistent with the recent experiments, and some of our results fall outside the region of validity of collective pinning theory.

关键词： strength theory force

Path Integral Approach for Multi-dimensional Polarons in a Symmetric Quantum Dot

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Chinese Physics Letters 1998年第8期15卷 585-587页

作者： CHEN Qing-hu REN Yu-hang cao yi-gang JIAO Zheng-kuan Department of Physics Zhejiang UniversityHangzhou 310027

Within the framework of Feynman-Haken path-integral theory,the general expression of the ground-state energy for multi-dimensional polarons in symmetric quantum dots for arbitrary electron-phonon coupling constants are ***,in the weak-coupling limit,the previous results by the second-order Rayleigh-Schrodinger perturbative theory are completely *** interestingly,the extended-and localized-state solutions to the ground-state energy are obtained analytically.

关键词： coupling dimensional arbitrary

不同力程排斥相互作用胶体粒子系统的摩擦特性

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物理学报 2024年第15期73卷 141-146页

作者：段浩炀杨柯欣曹义刚郑州大学物理学院:中原之光实验室郑州450001

利用朗之万分子动力学,数值研究了无序点钉扎衬底上二维胶体粒子系统的摩擦特性.本文考虑了三种不同的模型胶体粒子系统,每种系统中胶体粒子之间的相互作用均被模拟为两种不同力程的排斥势.研究发现:每种模型系统均存在两个最大静摩擦力... 详细信息

利用朗之万分子动力学,数值研究了无序点钉扎衬底上二维胶体粒子系统的摩擦特性.本文考虑了三种不同的模型胶体粒子系统,每种系统中胶体粒子之间的相互作用均被模拟为两种不同力程的排斥势.研究发现:每种模型系统均存在两个最大静摩擦力(第一最大静摩擦力f_(c1)^(d)和第二最大静摩擦力f_(c2)^(d));力程相近的短程排斥相互作用之间的干涉会导致粒子间排斥增强,从而导致f_(c1)^(d)的明显降低和f_(c2)^(d)以上沿外场驱动力方向上运动有序的加强.本文的研究结果有助于揭示具有不同力程相互作用胶体粒子系统的摩擦机制.

关键词：摩擦胶体塑性流动运动有序

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界面张力对Rayleigh-Taylor不稳定性的影响

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物理学报 2013年第21期62卷 252-258页

作者：夏同军董永强曹义刚郑州大学物理工程学院郑州450001 甘肃民族师范学院物理与水电系合作747000 许昌学院电信学院许昌461000

将具有简单速度势的Layzer模型和Zufiria模型推广至非理想流体情况,并分别利用这两种模型研究了界面张力对Rayleigh-Taylor不稳定性的影响.首先得到了两种模型下气泡的渐近速度和渐近曲率的解析表达式;其次系统研究了界面张力对气泡的... 详细信息

将具有简单速度势的Layzer模型和Zufiria模型推广至非理想流体情况,并分别利用这两种模型研究了界面张力对Rayleigh-Taylor不稳定性的影响.首先得到了两种模型下气泡的渐近速度和渐近曲率的解析表达式;其次系统研究了界面张力对气泡的渐近速度和渐近曲率的影响;最后将两种模型进行了比较,并将气泡的渐近速度和数值模拟进行了比较.研究表明:界面张力压低了气泡的速度,但对曲率没有影响;利用简单速度势的Layzer模型所得的气泡的渐近速度比复杂速度势的Layzer模型的值小,但是比Zufiria模型的值大;当阿特伍德数等于1时,简单速度势的Layzer模型和复杂速度势的Layzer模型给出的结果一致.

关键词： Rayleigh—Taylor不稳定性界面张力 Layzer模型 Zufiria模型

热传导对横截面不同的直管道中Kelvin-Helmholtz不稳定性的影响

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物理学报 2022年第9期71卷 191-197页

作者：曹义刚付萌萌杨喜昶李登峰王晓霞郑州大学物理学院郑州450001

Kelvin-Helmholtz不稳定性(KHI)增长的动力学分析是一个活跃的研究领域.本文解析研究了流体在横截面不同的直管道中流动时,热传导对KHI的影响.结果表明:管道中上下流体的界面相对切向速度会随着波数的增加先增加后减小,并且小的界面热... 详细信息

Kelvin-Helmholtz不稳定性(KHI)增长的动力学分析是一个活跃的研究领域.本文解析研究了流体在横截面不同的直管道中流动时,热传导对KHI的影响.结果表明:管道中上下流体的界面相对切向速度会随着波数的增加先增加后减小,并且小的界面热传导系数导致相对切向速度随波数的减小更多,不同于横截面相同的直管道结果.另外,热传导会提高KHI的增长率,与横截面相同的直管道一致.研究结果可以为实际管道中流体不稳定性的分析以及管道的通风设计和供暖等工程研究提供一定参考.

关键词： Kelvin-Helmholtz不稳定性热传导界面热传导系数

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九龙选煤厂煤泥水系统的技术改造

河北煤炭 2007年第5期 26-27页

作者：曹艺刚陈乃东峰峰集团九龙选煤厂河北邯郸056301

分析了九龙选煤厂洗水循环系统现状及存在问题,提出了对煤泥水系统的改造方案。

关键词：煤泥水系统快开压滤机高效浓缩机改造

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无序衬底上二维磁化胶体的脱钉特性

河南大学学报（自然科学版） 2008年第4期38卷 360-362页

作者：董永强张元敏曹义刚许昌学院电信学院河南许昌461000 郑州大学物理工程学院郑州450001

利用朗之万分子动力学,数值研究无序衬底上二维磁化胶体的脱钉特性.发现衬底强度对磁化胶体的脱钉产生重要影响.随着衬底强度的提高,磁化胶体的脱钉存在从弹性到塑性的渡越.

关键词：磁化胶体弹性脱钉塑性脱钉

Small extracellular vesicles derived from cerebral endothelial cells with elevated microRNA 27a promote ischemic stroke recovery

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Neural Regeneration Research 2025年第1期20卷 224-233页

作者： yi Zhang Zhongwu Liu Michael Chopp Michael Millman Yanfeng Li Pasquale Cepparulo Amy Kemper Chao Li Li Zhang Zheng gang Zhang Department of Neurology Henry Ford HospitalDetroitMIUSA Department of Physics Oakland UniversityRochesterMIUSA Department of Pathology Henry Ford HospitalDetroitMIUSA Division of Pharmacology Department of NeuroscienceReproductive and Dentistry SciencesSchool of MedicineUniversity of Naples“Federico Ⅱ”NaplesItaly

Axonal remodeling is a critical aspect of ischemic brain repair processes and contributes to spontaneous functional *** previous in vitro study demonstrated that exosomes/small extracellular vesicles(sEVs)isolated from cerebral endothelial cells(CEC-sEVs)of ischemic brain promote axonal growth of embryonic cortical neurons and that microRNA 27a(miR-27a)is an elevated miRNA in ischemic *** the present study,we investigated whether normal CEC-sEVs engineered to enrich their levels of miR-27a(27a-sEVs)further enhance axonal growth and improve neurological outcomes after ischemic stroke when compared with treatment with non-engineered CEC-sEVs.27a-sEVs were isolated from the conditioned medium of healthy mouse CECs transfected with a lentiviral miR-27a expression *** EVs isolated from CECs transfected with a scramble vector(Scra-sEVs)were used as a *** male mice were subjected to permanent middle cerebral artery occlusion and then were randomly treated with 27a-sEVs or *** array of behavior assays was used to measure neurological *** with treatment of ischemic stroke with Scra-sEVs,treatment with 27a-sEVs significantly augmented axons and spines in the peri-infarct zone and in the corticospinal tract of the spinal grey matter of the denervated side,and significantly improved neurological *** vitro studies demonstrated that CEC-sEVs carrying reduced miR-27a abolished 27a-sEV-augmented axonal *** analysis revealed that 27a-sEVs systemically administered preferentially localized to the pre-synaptic active zone,while quantitative reverse transcription-polymerase chain reaction and Western Blot analysis showed elevated miR-27a,and reduced axonal inhibitory proteins Semaphorin 6A and Ras Homolog Family Member A in the peri-infarct *** of the Clathrin-dependent endocytosis pathway substantially reduced neuronal internalization of *** data provide evidence that 27a-sEVs have

关键词： axonal remodeling cerebral endothelial cells exosomes miR-27a mitochondria Semaphorin 6A small extracellular vesicles stroke