arXiv - PHYS - Soft Condensed Matter最新文献_第8页

Neural density functional theory of liquid-gas phase coexistence 液-气相共存的神经密度泛函理论

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-28 DOI: arxiv-2408.15835

Florian Sammüller, Matthias Schmidt, Robert Evans

{"title":"Neural density functional theory of liquid-gas phase coexistence","authors":"Florian Sammüller, Matthias Schmidt, Robert Evans","doi":"arxiv-2408.15835","DOIUrl":"https://doi.org/arxiv-2408.15835","url":null,"abstract":"We use supervised machine learning together with the concepts of classical\u0000density functional theory to investigate the effects of interparticle\u0000attraction on the pair structure, thermodynamics, bulk liquid-gas coexistence,\u0000and associated interfacial phenomena in many-body systems. Local learning of\u0000the one-body direct correlation functional is based on Monte Carlo simulations\u0000of inhomogeneous systems with randomized thermodynamic conditions, randomized\u0000planar shapes of the external potential, and randomized box sizes. Focusing on\u0000the prototypical Lennard-Jones system, we test predictions of the resulting\u0000neural attractive density functional across a broad spectrum of physical\u0000behaviour associated with liquid-gas phase coexistence in bulk and at\u0000interfaces. We analyse the bulk radial distribution function $g(r)$ obtained\u0000from automatic differentiation and the Ornstein-Zernike route and determine i)\u0000the Fisher-Widom line, i.e. the crossover of the asymptotic (large distance)\u0000decay of $g(r)$ from monotonic to oscillatory, ii) the (Widom) line of maximal\u0000correlation length, iii) the line of maximal isothermal compressibility and iv)\u0000the spinodal by calculating the poles of the structure factor in the complex\u0000plane. The bulk binodal and the density profile of the free liquid-gas\u0000interface are obtained from density functional minimization and the\u0000corresponding surface tension from functional line integration. We also show\u0000that the neural functional describes accurately the phenomena of drying at a\u0000hard wall and of capillary evaporation for a liquid confined in a slit pore.\u0000Our neural framework yields results that improve significantly upon standard\u0000mean-field treatments of interparticle attraction. Comparison with independent\u0000simulation results demonstrates a consistent picture of phase separation even\u0000when restricting the training to supercritical states only.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220677","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Transients in shear thickening suspensions: when hydrodynamics matters 剪切增稠悬浮液中的瞬态：流体力学的重要性

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-27 DOI: arxiv-2408.15130

Shivakumar Athani, Bloen Metzger, Yoël Forterre, Romain Mari

引用次数: 0

Phase behavior of symmetric diblock copolymers under 3D soft confinement 三维软约束下对称二嵌段共聚物的相行为

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-27 DOI: arxiv-2408.14863

Zhijuan He, Jin Huang, Kai Jiang, An-Chang Shi

{"title":"Phase behavior of symmetric diblock copolymers under 3D soft confinement","authors":"Zhijuan He, Jin Huang, Kai Jiang, An-Chang Shi","doi":"arxiv-2408.14863","DOIUrl":"https://doi.org/arxiv-2408.14863","url":null,"abstract":"The phase behavior of symmetric diblock copolymers under three-dimensional\u0000(3D) soft confinement is investigated using the self-consistent field theory.\u0000The soft confinement is realized in binary blends composed AB diblock\u0000copolymers and C homopolymers, where the copolymers self-assemble to form a\u0000droplet embedded in the homopolymer matrix. The phase behavior of the confined\u0000block copolymers is regulated by the degree of confinement and the selectivity\u0000of the homopolymers, resulting in a rich variety of novel structures. When the\u0000C homopolymers are neutral to the A- and B-blocks, stacked lamellae (SL) are\u0000formed where the number of layers increases with the droplet volume, resulting\u0000in a morphological transition sequence from Janus particle to square SL. When\u0000the C homopolymers are strongly selective to the B-blocks, a series of\u0000non-lamellar morphologies, including onion-, hamburger-, cross-, ring-, and\u0000cookie-like structures, are observed. A detailed free energy analysis reveals a\u0000first-order reversible transformation between SL and onion-like (OL) structures\u0000when the selectivity of the homopolymers is changed. Our results provide a\u0000comprehensive understanding of how various factors, such as the copolymer\u0000concentration, homopolymer chain length, degree of confinement, homopolymer\u0000selectivity, affect the self-assembled structures of diblock copolymers under\u0000soft 3D confinement.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"38 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220678","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Phantom chain simulations for fracture of star polymer networks on the effect of arm molecular weight 关于臂分子量影响的星形聚合物网络断裂幻影链模拟

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-26 DOI: arxiv-2408.14058

Yuichi Masubuchi

{"title":"Phantom chain simulations for fracture of star polymer networks on the effect of arm molecular weight","authors":"Yuichi Masubuchi","doi":"arxiv-2408.14058","DOIUrl":"https://doi.org/arxiv-2408.14058","url":null,"abstract":"Despite many efforts, the fracture of network polymers under extension is yet\u0000to be elucidated. This study investigated the effect of strand molecular weight\u0000on the fracture characteristics of the networks made from star-branched\u0000prepolymers with various node functionalities $3 le f le 8$ and conversion\u0000ratios $0.6 le {phi}_c le 0.95$ via molecular simulations with phantom\u0000chains. The networks were created via end-linking reactions of star polymers\u0000with the arm molecular weight $N_a$ = 2, 5, and 10, simulated by a Brownian\u0000dynamics scheme. The cycle rank of the percolated network ${xi}$ was entirely\u0000consistent with the mean-field theory, implying that the reaction occurred\u0000independently and the network connectivity was statistically fair. Afterward,\u0000the networks were alternatively subjected to energy minimization and uniaxial\u0000stretch until the break. From the stress-strain curves recorded during the\u0000stretch, the stretch and stress at the break, ${lambda}_b$ and ${sigma}_b$,\u0000and work for fracture $W_b$ were obtained. For these values, the following\u0000relations were found: ${lambda}_b sim N_a^{(1/2)} {xi}^{(-1/3)}$,\u0000${sigma}_b sim {nu}_{br} N_a^{(4/3)} {xi}^{(2/3)}$, and $W_b sim\u0000{nu}_{br} N_a^{(4/3)} {xi}^{(2/3)}$, where ${nu}_{br}$ is the branch point\u0000density.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"172 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Achieving designed texture and flows in bulk active nematics using optimal control theory 利用最优控制理论实现散装主动线束中的设计纹理和流动

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-26 DOI: arxiv-2408.14596

Saptorshi Ghosh, Aparna Baskaran, Michael F. Hagan

{"title":"Achieving designed texture and flows in bulk active nematics using optimal control theory","authors":"Saptorshi Ghosh, Aparna Baskaran, Michael F. Hagan","doi":"arxiv-2408.14596","DOIUrl":"https://doi.org/arxiv-2408.14596","url":null,"abstract":"Being intrinsically nonequilibrium, active materials can potentially perform\u0000functions that would be thermodynamically forbidden in passive materials.\u0000However, active systems have diverse local attractors that correspond to\u0000distinct dynamical states, many of which exhibit chaotic turbulent-like\u0000dynamics and thus cannot perform work or useful functions. Designing such a\u0000system to choose a specific dynamical state is a formidable challenge.\u0000Motivated by recent advances enabling opto-genetic control of experimental\u0000active materials, we describe an optimal control theory framework that\u0000identifies a spatiotemporal sequence of light-generated activity that drives an\u0000active nematic system toward a prescribed dynamical steady-state. Active\u0000nematics are unstable to spontaneous defect proliferation and chaotic streaming\u0000dynamics in the absence of control. We demonstrate that optimal control theory\u0000can compute activity fields that redirect the dynamics into a variety of\u0000alternative dynamical programs and functions. This includes dynamically\u0000reconfiguring between states, and selecting and stabilizing emergent behaviors\u0000that do not correspond to attractors, and are hence unstable in the\u0000uncontrolled system. Our results provide a roadmap to leverage optical control\u0000methods to rationally design structure, dynamics, and function in a wide\u0000variety of active materials.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"30 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142227388","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Liquid-liquid phase separation at the interface of an evaporating droplet; formation of a regular lattice pattern 蒸发液滴界面上的液-液相分离；形成规则的晶格图案

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-26 DOI: arxiv-2408.14129

Vahid Nasirimarekani

引用次数: 0

Controlling assembly and oscillations of elastic membranes with an active fluid 用活性流体控制弹性膜的组装和振荡

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-26 DOI: arxiv-2408.14699

John Berezney, Sattvic Ray, Itamar Kolvin, Mark Bowick, Seth Fraden, Zvonimir Dogic

{"title":"Controlling assembly and oscillations of elastic membranes with an active fluid","authors":"John Berezney, Sattvic Ray, Itamar Kolvin, Mark Bowick, Seth Fraden, Zvonimir Dogic","doi":"arxiv-2408.14699","DOIUrl":"https://doi.org/arxiv-2408.14699","url":null,"abstract":"We use the chaotic flows generated by a microtubule-based active fluid to\u0000assemble self-binding actin filaments into a thin elastic sheets. Starting from\u0000a uniformly dispersed state, active flows drive the motion of actin filaments,\u0000inducing their bundling and formation of bundle-bundle connections that\u0000ultimately generate an elastic network. The emerging network separates from the\u0000active fluid to form a thin elastic sheets suspended at the sample midplane. At\u0000intermediate times, the active fluid drives large in-plane and out-of-plane\u0000deformations of the elastic sheet which are driven by low-energy bending modes.\u0000Self-organized sheets eventually exhibit centimeter-sized global spontaneous\u0000oscillations and traveling waves, despite being isotropically driven on micron\u0000lengths by the active fluid. The active assembly generates diverse network\u0000structures which are not easily realizable with conventional paradigms of\u0000equilibrium self-assembly and materials processing. Self-organized mechanical\u0000sheets pose a challenge for understanding of how a hierarchy of structure,\u0000mechanics, and dynamics emerges from a largely structureless initial suspension\u0000of active and passive microscopic components.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"4 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142220709","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluating fracture energy predictions using phase-field and gradient-enhanced damage models for elastomers 利用弹性体相场和梯度增强损伤模型评估断裂能量预测

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-09 DOI: arxiv-2408.05162

S. Mohammad Mousavi, Ida Ang, Jason Mulderrig, Nikolaos Bouklas

{"title":"Evaluating fracture energy predictions using phase-field and gradient-enhanced damage models for elastomers","authors":"S. Mohammad Mousavi, Ida Ang, Jason Mulderrig, Nikolaos Bouklas","doi":"arxiv-2408.05162","DOIUrl":"https://doi.org/arxiv-2408.05162","url":null,"abstract":"Recently, the phase field method has been increasingly used for brittle\u0000fractures in soft materials like polymers, elastomers, and biological tissues.\u0000When considering finite deformations to account for the highly deformable\u0000nature of soft materials, the convergence of the phase-field method becomes\u0000challenging, especially in scenarios of unstable crack growth. To overcome\u0000these numerical difficulties, several approaches have been introduced, with\u0000artificial viscosity being among the most widely utilized. This study\u0000investigates the energy release rate due to crack propagation in hyperelastic\u0000nearly-incompressible materials and compares the phase-field method and a novel\u0000gradient-enhanced damage (GED) approach. First, we simulate unstable loading\u0000scenarios using the phase-field method, which leads to convergence problems. To\u0000address these issues, we introduce artificial viscosity to stabilize the\u0000problem and analyze its impact on the energy release rate utilizing a domain\u0000J-integral approach giving quantitative measurements during crack propagation.\u0000It is observed that the measured energy released rate during crack propagation\u0000does not comply with the imposed critical energy release rate, and shows\u0000non-monotonic behavior. In the second part of the paper, we introduce a novel\u0000stretch-based GED model as an alternative to the phase-field method for\u0000modeling crack evolution in elastomers. It is demonstrated that in this method,\u0000the energy release rate can be obtained as an output of the simulation rather\u0000than as an input which could be useful in the exploration of rate-dependent\u0000responses, as one could directly impose chain-level criteria for damage\u0000initiation. We show that while this novel approach provides reasonable results\u0000for fracture simulations, it still suffers from some numerical issues that\u0000strain-based GED formulations are known to be susceptible to.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"22 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141937370","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A patchy-particle 3-dimensional octagonal quasicrystal 斑状粒子三维八边形准晶体

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-09 DOI: arxiv-2408.05003

Akie Kowaguchi, Savan Mehta, Jonathan P. K. Doye, Eva G. Noya

引用次数: 0

Molecular dynamics simulations of head-on low-velocity collisions between particles 粒子间正面低速碰撞的分子动力学模拟

arXiv - PHYS - Soft Condensed Matter Pub Date : 2024-08-08 DOI: arxiv-2408.04164

Yuki Yoshida, Eiichiro Kokubo, Hidekazu Tanaka

{"title":"Molecular dynamics simulations of head-on low-velocity collisions between particles","authors":"Yuki Yoshida, Eiichiro Kokubo, Hidekazu Tanaka","doi":"arxiv-2408.04164","DOIUrl":"https://doi.org/arxiv-2408.04164","url":null,"abstract":"The particle contact model is important for powder simulations. Although\u0000several contact models have been proposed, their validity has not yet been well\u0000established. Therefore, we perform molecular dynamics (MD) simulations to\u0000clarify the particle interaction. We simulate head-on collisions of two\u0000particles with impact velocities less than a few percent of the sound velocity\u0000to investigate the dependence of the interparticle force and the coefficient of\u0000restitution (COR) on the impact velocity and particle radius. In this study, we\u0000treat particles with a radius of 10-100 nm and perform simulations. We find\u0000that the interparticle force exhibits hysteresis between the loading and\u0000unloading phases. Larger impact velocities result in strong hysteresis and\u0000plastic deformation. For all impact velocities and particle radii, the\u0000coefficient of restitution is smaller than that given by the\u0000Johnson-Kendall-Robert theory. An inelastic contact model cannot reproduce our\u0000MD simulations. In particular, the COR is significantly reduced when the impact\u0000velocity exceeds a certain value. This significant energy dissipation cannot be\u0000explained even by the contact models including plastic deformation. We also\u0000find that the COR increases with increasing particle radius. We also find that\u0000the previous contact models including plastic deformation cannot explain the\u0000strong energy dissipation obtained in our MD simulations, although they agree\u0000with the MD results for very low impact velocities. Accordingly, we have\u0000constructed a new dissipative contact model in which the dissipative force\u0000increases with the stress generated by collisions. The new stress dependent\u0000model successfully reproduces our MD results over a wider range of impact\u0000velocities than the conventional models do. In addition, we proposed another,\u0000simpler, dissipative contact model that can also reproduce the MD results.","PeriodicalId":501146,"journal":{"name":"arXiv - PHYS - Soft Condensed Matter","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2024-08-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141937372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0