Article
Polymer Science
Antonio Lamura
Summary: The dynamical response of a tethered semiflexible polymer with self-attractive interactions under an external force field was numerically investigated by varying stiffness and self-interaction strength. Different parameters led to various transitions and morphological changes in the polymer chain. The study showed that the external force had significant effects on the conformation and deformation of the polymer chain.
Article
Thermodynamics
Yee-Ting Lee
Summary: This study investigates the thermal-fluid behaviors of subcooled flow boiling in microchannels through computational and experimental approaches. A computational fluid dynamics (CFD) model is used to simulate the interfacial movements between liquid water and vapor, while experiments are conducted to measure heat transfer and pressure drop outcomes. The results show that a microchannel design with an aspect ratio of 5.0 achieves satisfactory overall thermal and frictional outcomes.
INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER
(2023)
Article
Chemistry, Physical
Maxim D. Malyshev, Daria Guseva, Valentina V. Vasilevskaya, Pavel Komarov
Summary: This study investigated the mechanical properties of epoxy resin filled with clay nanoparticles of various shapes and contents. It was found that the chemical cross-linking between nanoparticles and the polymer matrix enhanced the composite material's performance, with different nanoparticle shapes showing distinct effects on the elastic modulus.
Article
Mechanics
Anoshanth Jeyasountharan, Gaetano D'Avino, Francesco Del Giudice
Summary: In this study, the effect of confinement ratio on the self-ordering dynamics of particles suspended in a viscoelastic liquid and flowing in a microfluidic channel is investigated through numerical simulations and experiments. The results show that the confinement ratio affects the self-ordering distance and relative particle velocity.
Article
Chemistry, Analytical
Dustin R. Ray, Debendra K. Das
Summary: In this study, two new correlations based on velocity and fRe criteria were developed for the hydrodynamic entrance length in rectangular microchannels with low Reynolds numbers (Re < 100) using a vast amount of numerical data.
Article
Polymer Science
Pavel V. Komarov, Pavel G. Khalatur, Alexei R. Khokhlov
Summary: A coarse-grained model is proposed for mesoscale simulation of nanocomposites with magnetic nanoparticles embedded in a highly cross-linked polymer network. The simulations using reactive dissipative particle dynamics show that the ordering of nanoparticles induces anisotropy in mechanical properties, affecting the network topology and increasing the Young's modulus. The role of the polymer/MNP interface is also studied, revealing its additional contribution to the tensile rigidity of composites.
POLYMERS FOR ADVANCED TECHNOLOGIES
(2021)
Article
Chemistry, Physical
Dario Vincenzi
Summary: Research shows that internal friction does not change the critical Weissenberg number for the coil-stretch transition of polymers, but it does steepen the slope of the extension probability distribution, making the transition more pronounced.
Article
Physics, Multidisciplinary
M. Reza Shaebani, Janos Torok, Maniya Maleki, Mahnoush Madani, Matt Harrington, Allyson Rice, Wolfgang Losert
Summary: The research found that the flow profile is independent of gravity for geometries with a free top surface; however, under a confining pressure or if the sheared layer withstands the weight of the upper layers, increasing gravity promotes the transition from closed shear zones to open ones. The center position and width of the shear zone, as well as the axial angular velocity at the top surface, follow universal scaling laws.
PHYSICAL REVIEW LETTERS
(2021)
Article
Physics, Multidisciplinary
Saraswat Bhattacharyya, Julia M. Yeomans
Summary: We present an extension of continuum theories of active nematohydrodynamics to investigate the behavior of a two-fluid mixture with separate velocity fields for each component. The interaction between active anchoring and active flows driven by concentration gradients leads to microphase separation in an active nematic fluid mixed with an isotropic fluid. These findings have potential implications for understanding cell sorting processes and the formation of lipid rafts in cell membranes.
PHYSICAL REVIEW LETTERS
(2023)
Article
Thermodynamics
Reza Balali Dehkordi, Davood Toghraie, Mohammad Hashemian, Farshid Aghadavoudi, Mohammad Akbari
Summary: The study examines the effects of external electrostatic force and external electrical field on Fe3O4 nanoparticles in a copper microchannel, showing that the external electrical field plays a significant role in the agglomeration process in atomic structures, with an increase in field leading to an increase in the time required for the agglomeration process.
INTERNATIONAL COMMUNICATIONS IN HEAT AND MASS TRANSFER
(2021)
Article
Physics, Fluids & Plasmas
Roxane Letournel, Ludovic Goudenege, Remi Zamansky, Aymeric Vie, Marc Massot
Summary: The paper proposes a set of requirements for models designed within the Lagrangian framework and explores multifractal stochastic processes and Gaussian multiplicative chaos formalism to retrieve multifractal properties in simulating intermittency. Additionally, a stochastic model is proposed to approximate fractional Brownian motion by an infinite weighted sum of correlated Ornstein-Uhlenbeck processes, and a new simulation approach is designed for intermittency processes.
Article
Chemistry, Physical
Nicholas C. Craven, Justin B. Gilmer, Caroline J. Spindel, Andrew Z. Summers, Christopher R. Iacovella, Clare McCabe
Summary: This study utilizes molecular dynamics simulations to investigate the self-assembly of anisotropically coated patchy nanoparticles, revealing different phases formed based on various parameters. Correlation analysis identifies key predictors of bulk phase behavior, offering a powerful approach for future screening of these materials.
JOURNAL OF CHEMICAL PHYSICS
(2021)
Article
Thermodynamics
Abdolmajid Taghipour, Arash Karimipour, Masoud Afrand, Somaye Yaghoubi, Mohammad Akbari
Summary: This study investigates the dynamical properties of Ar and O-2 flows using DPD and MD simulation approaches, showing variations in velocity and temperature with decreasing microchannel size.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2021)
Article
Polymer Science
Yaguang Sun, Kaiwei Wan, Wenhui Shen, Jianxin He, Tong Zhou, Hui Wang, Hua Yang, Xinghua Shi
Summary: Recycling and reprocessing of conventional thermosetting polymers have gained attention due to environmental concerns. This study focuses on covalent adaptable networks (CANs) which incorporate functional groups capable of reversible exchange reactions into polymer networks, altering the topology arrangement and achieving stress relaxation. The researchers developed a machine-learning force field to describe the exchange reactions of polyimine CANs and provided insights into reaction mechanisms and energy profiles through enhanced sampling methods.
Review
Construction & Building Technology
Katerina Ioannidou, Christophe Labbez, Enrico Masoero
Summary: This manuscript reviews the current state of the art in coarse-grained and mesoscale simulations of C-S-H, and highlights opportunities for future research.
CEMENT AND CONCRETE RESEARCH
(2022)
Article
Chemistry, Physical
Judit Clopes, Gerhard Gompper, Roland G. Winkler
Summary: This study investigates the properties of microswimmer dumbbells consisting of pusher-puller pairs using mesoscale hydrodynamic simulations. The simulations reveal that the flow fields of the squirmers strongly influence the orientation of their propulsion directions, fluctuations, and swimming behavior. The magnitude of the active stresses only weakly affects the properties of pusher-puller pairs with equal stress magnitudes, but for non-equal stress magnitudes, strong orientational correlations are observed. The active motion of the dumbbells is influenced by these correlations, with faster motion for strong pushers and slower motion for strong pullers.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Physics, Multidisciplinary
Segun Goh, Roland G. Winkler, Gerhard Gompper
Summary: This study reveals that pursuit performance depends on the interplay between self-propulsion, active reorientation, limited maneuverability, and random noise. Noise has two opposing effects: disturbing regular orbits around the target and slowing down pursuit. The mean pursuer-target distance and mean first-passage time exhibit a universal scaling behavior, but are modified by factors such as thermal or active noise and the velocity ratio between target and pursuer.
NEW JOURNAL OF PHYSICS
(2022)
Article
Chemistry, Multidisciplinary
Jiarul Midya, Thorsten Auth, Gerhard Gompper
Summary: Transport of particles across lipid-bilayer membranes is crucial for cells to interact with their environment. While previous studies have focused on hard particles, this research investigates the wrapping process for deformable particles, specifically vesicles. The findings highlight the importance of particle softness in determining the stability and interaction behavior of wrapped vesicles, providing insights for the design of deformable particles for medical applications.
Article
Physics, Multidisciplinary
Marielle Gassner, Segun Goh, Gerhard Gompper, Roland G. Winkler
Summary: This study theoretically and through simulations analyzes the properties of a cognitive, self-propelled, and self-steering particle in the presence of a stationary target, with a focus on the competition between confinement, activity, and steering. The pursuer is modeled as an intelligent active Ornstein-Uhlenbeck particle (iAOUP) confined in a harmonic potential. Universal scaling regimes for the pursuer-target distance are found for the free pursuer, with the Pe'clet number and maneuverability as key factors. Steering leads to a constant mean-distance regime that widens with increasing maneuverability. Confinement strongly impacts propulsion direction and results in scaling behaviors similar to those without confinement but dependent on confinement strength at large Pe'clet numbers.
Article
Multidisciplinary Sciences
Xiaoyan Liu, Thorsten Auth, Nabanita Hazra, Morten Frend Ebbesen, Jonathan Brewer, Gerhard Gompper, Jerome J. Crassous, Emma Sparr
Summary: This paper investigates how the wrapping of colloidal particles by lipid membranes can be controlled by various factors such as particle shape, particle-membrane adhesion energy, membrane phase behavior, and membrane-bending rigidity. The study shows that ellipsoidal microgel particles are more likely to form deep-wrapped states compared to spherical particles. The findings have implications for the design of novel biomaterials and therapeutic applications involving nanoparticle-membrane interactions.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Physics, Multidisciplinary
Segun Goh, Roland G. Winkler, Gerhard Gompper
Summary: This study investigates the pursuit behavior of pursuer-target pairs with implicit sensing mechanism and limited hydrodynamic steering abilities of the pursuer. The findings suggest that stable cooperatively moving states can be achieved depending on the nature of the microswimmer propulsion and the velocity-adaptation scheme.
COMMUNICATIONS PHYSICS
(2023)
Article
Chemistry, Physical
Priyanka Iyer, Gerhard Gompper, Dmitry A. Fedosov
Summary: Recent advances in micro- and nano-technologies have made it possible to construct complex active systems using biological and synthetic materials. This study investigates the behavior of active vesicles, which are composed of a membrane enclosing self-propelled particles and exhibit characteristics similar to biological cells. The adhesion of self-propelled particles to the membrane significantly influences the shape and dynamics of the vesicles, providing an additional parameter for controlling their behavior.
Article
Physics, Multidisciplinary
Joscha Mecke, Yongxiang Gao, Carlos A. Ramirez Medina, Dirk G. A. L. Aarts, Gerhard Gompper, Marisol Ripoll
Summary: This article reports the simultaneous occurrence and relation of two seemingly separate phenomena: active turbulence and odd viscosity, in a chiral active fluid composed of standing and spinning colloidal rods and in simulations for synchronously rotating hard discs in a hydrodynamic explicit solvent.
COMMUNICATIONS PHYSICS
(2023)
Correction
Chemistry, Physical
Priyanka Iyer, Gerhard Gompper, Dmitry A. A. Fedosov
Article
Chemistry, Physical
Priyanka Iyer, Gerhard Gompper, Dmitry A. Fedosov
Summary: This study investigates the behavior of active vesicles through simulations, analyzing the deformations of membranes, clustering and mobility of SPPs. The results reveal a feedback mechanism between membrane curvature, particle clustering, and changes in vesicle shape due to SPP activity.
Article
Chemistry, Physical
Rajendra Singh Negi, Roland G. Winkler, Gerhard Gompper
Summary: This study investigates self-steering active Brownian particle systems through simulations and discovers self-organized large-scale structures that depend on parameter values and excluded-volume interactions. The analysis of particle dynamics reveals ABP-like behaviors in dilute systems and the worm phase. In densely packed structures, the active diffusion coefficient is significantly smaller and depends on the number of particles in the cluster. The study also explores the interplay between ABP-characteristic interactions and cognitive-based interactions and navigation.
Article
Physics, Fluids & Plasmas
Christian A. Philipps, Gerhard Gompper, Roland G. Winkler
Summary: Analytical investigation of isolated semiflexible active polar ring polymers reveals that activity does not affect ring conformations but strongly impacts internal dynamics, showing characteristic time regimes that are absent in passive rings. Flexible rings exhibit activity-enhanced diffusive behavior on intermediate timescales, while semiflexible rings display ballistic motion. Additionally, a second active time regime emerges on longer timescales, with rings showing snake-like motion reminiscent of tank-treading rotational dynamics in shear flow.
Article
Physics, Fluids & Plasmas
Anil Kumar Dasanna, Alexis Darras, Thomas John, Gerhard Gompper, Lars Kaestner, Christian Wagner, Dmitry A. Fedosov
Summary: The erythrocyte sedimentation rate is commonly used as an indicator of cell aggregation and inflammation. This study investigated the relationship between fibrinogen concentration, microstructure of erythrocyte suspension, and erythrocyte sedimentation rate. The researchers found that an increase in attraction strength between cells led to a cell network with larger void spaces, resulting in faster sedimentation. These findings support the gel hypothesis in blood sedimentation interpretation.
Article
Physics, Fluids & Plasmas
Judit Clopes Llahi, Aitor Martin-Gomez, Gerhard Gompper, Roland G. Winkler
Summary: This study compares the properties of self-propelled and externally actuated active Brownian polymers in a fluid. By implementing a multiparticle collision (MPC) simulation, the conformational and dynamical properties of the active polymers, as well as their scaling behavior with respect to wave number and time dependence, are obtained. The suitability of the implementation is confirmed by comparing the simulation results with theoretical predictions.
