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Phase field simulation of dendrite growth under convection

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Acta Metallurgica Sinica(English Letters) 2010年第2期23卷 121-128页

作者： Yutian DING Xun.fcng yuan Tingbiao guo yong HU State Key Laboratory of Gansu Advanced Non-Ferrous Metal Materials Lanzhou University of TechnologyLanzhou 730050 China

The phase-field model coupled with a flow field was used to simulate the solidification of pure materials by the finite difference method. The effects of initial crystal radius, the space step and the interface thickness on the dendrite growth were studied. Results indicate that the grain grows into an equiaxial dendrite during free flow and into a typical branched structure under forced flow. The radius of an initial crystal can affect the growth of side-branches but not the stability of the dendrite＇s tip when an appropriate value is assigned to it. With an increase in space steps, side-branches appear at the upstream of the longitudinal principal branch and they grow rapidly. With an increase in the interface thickness, the trunk of the longitudinal upstream and lateral principal branches grow longer and become more slender while the number of secondary branches increases.

关键词： Phase field method Forced flow Dendrite growth Simulation

Control of Spiral Waves and Spatiotemporal Chaos by Exciting Travel Wave Trains

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Communications in Theoretical Physics 2005年第5X期44卷 858-862页

作者： yuan guo-yong WANG Guang-Rui CHEN Shi-Gang Department of Physics Hebei Normal University Shijiazhuang 050016 China Graduate School of the Chinese Academy of Engineering Physics P.O. Box 2101 Beijing 100088 China Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China

Spiral waves and spatiotemporal chaos usually are harmful and need to be suppressed. In this paper, a method is proposed to control them. Travel wave trains can be generated by periodic excitations near left boundary,spiral waves and spatiotemporal chaos can be eliminated by the trains for some certain excitation periods. Obvious resonant behavior can be observed from the relation between the periods of the trains and excitation ones. The method is against noise.

关键词： spatiotemporal chaos spiral waves control

Segmented Spiral Waves and Anti-phase Synchronization in a Model System with Two Identical Time-Delayed Coupled Layers

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Communications in Theoretical Physics 2008年第1期49卷 174-180页

作者： yuan guo-yong YANG Shi-Ping WANG Guang-Rui CHEN Shi-Gang Department of Physics Hebei Normal University Shijiazhuang 0500167 China Institute of Applied Physics and Computational Mathematics P.O. Box 8009 Beijing 100088 China

In this paper, we consider a model system with two identical time-delayed coupled layers. Synchronization and anti-phase synchronization are exhibited in the reactive system without diffusion term. New segmented spiral waves, which are constituted by many thin trips, are found in each layer of two identical time-delayed coupled layers, and are different from the segmented spiral waves in a water-in-oil aerosol sodium bis（2-ethylhexyl） sulfosuccinate （AOT） microemulsion （ME）（BZ-AOT system）, which consists of many small segments. ＂Anti-phase spiral wave synchronization＂ can be realized between the first layer and the second one. For different excitable parameters, we also give the minimum values of the coupling strength to generate segmented spiral waves and the tip orbits of spiral waves in the whole bilayer.

关键词： spiral wave synchronization anti-phase synchronization

A Deep Learning Estimation Method for Temperature-Induced Girder End Displacements of Suspension Bridges

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Structural Durability & Health Monitoring 2025年第2期19卷 307-325页

作者： Yao Jin yuan Ren Chong-yuan guo Chong Li Zhao-yuan guo Xiang Xu School of Transportation Southeast UniversityNanjing210096China Department of Engineering Guangzhou Expressway Operation Management Co.Ltd.Guangzhou510000China Department of Engineering CCCC Highway Bridge National Engineering Research Center Co.Ltd.Beijing100088China Department of Engineering Jiangsu Provincial Transportation Engineering Construction BureauNanjing210004China

To improve the accuracy of thermal response estimation and overcome the limitations of the linear regression model and Artificial Neural Network(ANN)model,this study introduces a deep learning estimation method specifically based on the Long Short-Term Memory(LSTM)network,to predict temperature-induced girder end displacements of the Dasha Waterway Bridge,a suspension bridge in ***,to enhance data quality and select target sensors,preprocessing based on the sigma rule and nearest neighbor interpolation is applied to the raw ***,to eliminate the high-frequency components from the displacement signal,the wavelet transform is ***,the linear regression model and ANN model are established,whose results do not meet the requirements and fail to address the time lag effect between temperature and *** study proceeds to develop the LSTM network model and determine the optimal parameters through hyperparameter sensitivity ***,the results of the LSTM network model are discussed by a comparative analysis against the linear regression model and ANN model,which indicates a higher accuracy in predicting temperatureinduced girder end displacements and the ability to mitigate the time-lag *** be more specific,in comparison between the linear regression model and LSTM network,the mean square error decreases from 6.5937 to 1.6808 and R2 increases from 0.683 to 0.930,which corresponds to a 74.51%decrease in MSE and a 36.14%improvement in *** to ANN,with an MSE of 4.6371 and an R2 of 0.807,LSTM shows a decrease in MSE of 63.75%and an increase in R2 of 13.23%,demonstrating a significant enhancement in predictive performance.

关键词： Suspension bridges thermal response girder end displacement deep learning

Tunable non-Markovian and quantum coherence in the single-qubit dephasing noise channel

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Science China(Physics,Mechanics & Astronomy) 2025年第3期68卷 92-101页

作者： Na-Na Zhang Chao-Yi Wu Xu Zhou Qi-yuan Liu Cheng-Ge Liu yong-Rui guo Ren-Pu Li School of Optoelectronic Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China Department of Physics Applied Optics Beijing Area Major LaboratoryBeijing Normal UniversityBeijing100875China

In this paper,we construct a single-qubit dephasing noise channel based on the nuclear magnetic resonance(NMR)system by employing the bath-engineering technology,and achieve the construction of the tunable non-Markovian environment in the dephasing noise *** findings indicate that for the single-qubit system,the transition of system dynamics from Markovian to non-Markovian can be achieved by adjusting the base frequency of the noise power ***,the base frequency corresponding to this phase transition point is not fixed,and there is a certain relationship between it and the total evolution time of the single-qubit *** our research,we discovered a fundamental relationship:if the single-qubit system dynamics undergoe a transition from Markovian to non-Markovian atω_(0) within 0-2t ms,shortening the evolution time to 0-t ms results in an increase of the phase transition point to 2ω_(0).This insight offers crucial guidance for artificially crafting non-Markovian environments across arbitrary time scales in single-qubit systems,and it is not limited by the type of *** from system dynamics,quantum coherence is also a focal point of our *** find that when the system dynamics exhibit non-Markovian behavior,the quantum coherence of the single-qubit system experiences ***,the timing of these coherence revivals aligns with the instants of the non-Markovianity ***,our research also serves as a pivotal foundation for the artificial manipulation and realization of quantum coherence revivals within diverse single-qubit systems.

关键词： dephasing noise channel non-Markovian quantum coherence

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Leber遗传性视神经病心血管并发症的研究进展

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中国全科医学 2017年第20期20卷 2543-2546页

作者：郭皓袁勇郭立昆明医科大学附属甘美医院心内科云南省昆明市650011 昆明医科大学第二附属医院急诊外科云南省昆明市650101 昆明医科大学第二附属医院放射科云南省昆明市650101

Leber遗传性视神经病(LHON)是最典型、最常见的线粒体遗传病之一,线粒体疾病常累及多个需高能代谢的组织和器官,尤以神经系统显著,其次也累及心肌、骨骼肌等。随着对LHON心血管并发症的不断深入研究,目前相继有关于心脏的神经系统受累... 详细信息

Leber遗传性视神经病(LHON)是最典型、最常见的线粒体遗传病之一,线粒体疾病常累及多个需高能代谢的组织和器官,尤以神经系统显著,其次也累及心肌、骨骼肌等。随着对LHON心血管并发症的不断深入研究,目前相继有关于心脏的神经系统受累、心肌病变和血管病变等心血管异常的报道,LHON的不同器官组织受累和外显发病提示,在临床工作中对LHON患者应常规进行心血管方面检查,同时也表明线粒体DNA突变致病的复杂性。

关键词：视神经萎缩,遗传性,Leber DNA,线粒体心血管系统并发症

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多可激性障碍下的螺旋波动力学

物理学报 2013年第16期62卷 45-54页

作者：袁国勇张焕王光瑞河北师范大学物理科学与信息工程学院石家庄050024 河北省新型薄膜材料实验室石家庄050024 北京应用物理与计算数学研究所北京100088

在许多实际可激系统中局部不均匀是广泛存在的,它们是螺旋波形成以及动力学行为改变的重要因素.本文研究了可激性障碍对螺旋波动力学行为的影响.研究表明,在障碍区域内可激性参数大于区域外情况下障碍会对其附近的螺旋波波头有吸引作用... 详细信息

在许多实际可激系统中局部不均匀是广泛存在的,它们是螺旋波形成以及动力学行为改变的重要因素.本文研究了可激性障碍对螺旋波动力学行为的影响.研究表明,在障碍区域内可激性参数大于区域外情况下障碍会对其附近的螺旋波波头有吸引作用,多局部障碍共存时吸引行为不仅依赖障碍分布,而且依赖障碍的大小以及区域内可激性参数的具体取值.通过抑制变量小值区域的变化分析了这些行为发生的原因.在障碍区域内可激性参数小于区域外情况下障碍对其近邻的螺旋波波头有排斥作用,排斥后波头的运动依赖初始螺旋波是刚性旋转的还是漫游的.多局部障碍共存时排斥作用对螺旋波动力学行为的改变依赖障碍的分布、大小与区域内可激性参数的具体取值以及初始螺旋波的类型.

关键词：螺旋波时空混沌可激性障碍

Synergistic mechanism of metal ions and sodium N-oleoylsarcosinate on flotation separation of lepidolite from feldspar

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Transactions of Nonferrous Metals Society of China 2025年第1期35卷 296-312页

作者： guo-yuan XIANG Rui-hua FAN Wen-tao ZHU Wei SUN Ren-ji ZHENG Zhi-yong GAO School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China Hunan International Joint Research Centre for Efficient and Clean Utilization of Critical Metal Mineral Resources Central South UniversityChangsha 410083China Engineering Research Center of Ministry of Education for Carbon Emission Reduction in Metal Resource Exploitation and Utilization Central South UniversityChangsha 410083China

The combined reagents of sodium N-oleoylsarcosinate(SNOS)with metal ions(Ca(Ⅱ),Mg(Ⅱ),Cu(Ⅱ),and Pb(Ⅱ))was employed to facilitate the separation of lepidolite from *** synergistic interaction mechanism of this combined reagent was systematically investigated via contact angle measurements,AFM,FTIR,species distribution calculations,and DFT *** results suggested that Ca(Ⅱ)exhibited the best selectivity for activating lepidolite *** was chemically adsorbed on the Ca(Ⅱ)-activated lepidolite surface with an adsorption energy of−1248.91 kJ/mol while a lower adsorption energy of−598.84 kJ/mol of SNOS on Ca(Ⅱ)-activated feldspar was ***,this combination of SNOS and Ca(Ⅱ)is a promising reagent scheme for the efficient recovery of lithium from aluminosilicate ore.

关键词： flotation lepidolite feldspar sodium N-oleoylsarcosinate metal ions

3D morphology of crab(Macrophthalmus japonicus) burrows from the Pearl River Delta front,China:The physicochemical factors,with implications for the rock record

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Journal of Palaeogeography 2025年第1期14卷 203-220页

作者： yuan-yuan Wang Ya-Bin Zhang Song-Lin Gou guo-Cheng Zhang Institute of Resource and Environment Henan Polytechnic University Henan International Joint Laboratory of Biogenic Traces and Sedimentary Minerals Henan Polytechnic University

Neoichnological characterization of modern depositional settings addresses the response of benthic animals to ecological conditions and their fluctuations, usually on a relatively short time scale. In this way, analogue models for interpretation of sedimentary strata in the geological record can be *** japonicus(De Haan, 1835), a crab, is commonly found in the Pearl River Delta front of southern China. The burrows of M. japonicus are vertical or inclined, I-, U-, Y-, J-and L-shaped tubes, and these are imaged in 7.5-cm-diameter sediment cores. The cores were studied by X-ray radiography, computed tomography, and VG Studio MAX reconstruction to obtain three-dimensional images for elaborate morphological study. This crab's burrows are analogous to the trace fossil Psilonichnus. Several environmental parameters, i.e., sediment grain size and its total organic carbon(TOC) content, and turbidity and salinity of water, have been measured. The results indicated that M. japonicus prefers to live in mesohaline water with turbidity levels of 20-170 NTU, where bioturbation is more abundant. It prefers to occur in mud and silty sand substrates, with TOC content decreasing as particle size increases. The sedimentary environment, grain size and ichnofacies of analogical trace fossils Psilonichnus are discussed which supports the interpretation that Psilonichnus is a good indicator of delta front environments.

关键词： Neoichnology Macrophthalmus japonicus Pearl River Delta front Physicochemical factor