Article
Chemistry, Multidisciplinary
Qingguang Xie, Jens Harting
Summary: This study reports the capillary assembly of magnetic ellipsoidal Janus particles at a fluid-fluid interface, where the particles can deform the interface and generate different structures depending on their tilt angle, and can be actively controlled by applying an external magnetic field.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Jacopo Vialetto, Fabrizio Camerin, Shivaprakash N. Ramakrishna, Emanuela Zaccarelli, Lucio Isa
Summary: The encapsulation of a rigid core within a soft polymeric shell allows obtaining composite colloidal particles with retained functional properties. The authors investigated the interfacial morphology of these particles and identified that the core properties, shell thicknesses, and grafting density can influence their conformation. By understanding their wetting behavior, these composite particles can be designed to exhibit specific inter-particle interactions for the stabilization of interfaces and the fabrication of tailored 2D materials with functional properties.
Review
Physics, Condensed Matter
Eduardo Guzman, Irene Abelenda-Nunez, Armando Maestro, Francisco Ortega, Andreas Santamaria, Ramon G. Rubio
Summary: This article explores the physico-chemical bases of particle-laden fluid/fluid interfaces and their ability to stabilize emulsions and foams. Experimental and analytical results using chemically isotropic spherical colloids provide reference for the development of novel interface-dominated devices.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Chemistry, Multidisciplinary
Anne C. Nickel, Andrey A. Rudov, Igor I. Potemkin, Jerome J. Crassous, Walter Richtering
Summary: This study compares the interfacial deformation and assembly of anisotropic core-shell and hollow microgels and highlights the importance of microgel shape and stiffness on their behavior at the interface.
Article
Engineering, Chemical
Ruihuan Cai, Hongyi Xiao, Ivan C. Christov, Yongzhi Zhao
Summary: The diffusion coefficient of nonspherical particles in shear flow was studied through discrete element method simulations. It was found that the particle aspect ratio strongly affects the diffusion coefficient by influencing particle orientation and alignment. A scaling law for the diffusion coefficient perpendicular to the flow direction was developed, which will be useful in developing continuum transport models for applications.
Article
Polymer Science
Weizhao Ren, Yongming Hong, Huidong Wei, Jianquan Xu, Cuiyun Zhang, Xianjing Zhou, Xinping Wang
Summary: The adsorbed polymer layer on the inorganic solid surface plays a crucial role in improving the physical properties of composite nanomaterials. By altering the structure of the adsorbed layer, the properties can be tuned. In this study, we investigated the adsorbed layers of poly(methyl methacrylate) (PMMA) on SiO2-Si substrates by varying the hydroxyl (OH) group content on the substrate surface. The results showed that the thickness of the adsorbed layers decreased with decreasing OH group content, and the flattened layer disappeared when the content was around 31%. The presence of OH groups controlled the formation of the adsorbed layer, providing anchor points through hydrogen bonding with the carbonyl groups in PMMA.
Article
Physics, Fluids & Plasmas
Hugo Chesneau, Hamza Chraibi, Nicolas Bertin, Julien Petit, Jean-Pierre Delville, Etienne Brasselet, Regis Wunenburger
Summary: We report on numerical simulation of fluid interface deformations induced by either acoustic or optical radiation pressure. Using dimensional analysis, we show that interface deformation morphogenesis is universal, i.e., depends on the same dimensionless parameters in acoustics and electromagnetics. The qualitative agreement between the numerical simulations and experiments demonstrates the leading role of the radiation pressure in morphogenesis of fluid interface deformations and the importance of the propagation-deformation interplay.
Article
Multidisciplinary Sciences
Steffen Bochenek, Fabrizio Camerin, Emanuela Zaccarelli, Armando Maestro, Maximilian M. Schmidt, Walter Richtering, Andrea Scotti
Summary: This study utilized neutron reflectometry to investigate the structure and responsiveness of microgels at the air-water interface. The results revealed that temperature only affects the portion of microgels in water, while the softness of the microgels has the strongest effect on their ability to protrude into the air.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Multidisciplinary
Anne C. Nickel, Timon Kratzenberg, Steffen Bochenek, Maximilian M. Schmidt, Andrey A. Rudov, Andreas Falkenstein, Igor I. Potemkin, Jerome J. Crassous, Walter Richtering
Summary: This study investigates the two-dimensional ordering of different core-shell microgels with varying softness and size at oil-water interfaces, revealing that softness affects the alignment of tip-to-tip or side-to-side ordering, i.e., the alignment mode, along with hardness and size. Thin and harder microgel shells lead to side-to-side ordering, while large, soft microgel shells result in tip-to-tip alignment.
Article
Mathematics, Interdisciplinary Applications
Shams Forruque Ahmed
Summary: In turbulent flow of fibre suspensions, solid particles like dust particles significantly affect the turbulent flow field in a rotational frame. This study aims to build a theoretical model for the energy motion of dusty turbulent flow of fibre suspensions in such a rotational frame. The newly derived equation considers the turbulent momentum equation in dusty fluid rotating flow of fibre suspensions, improving upon the previous model.
Article
Multidisciplinary Sciences
Erin G. Teich, K. Lawrence Galloway, Paulo E. Arratia, Danielle S. Bassett
Summary: The study focuses on the nature of yield in amorphous materials under stress, investigating the evolution of local structural homogeneity on an individual particle level and its relation to rearrangement, memory, and macroscale rheological measurements. The research defines a structural metric called crystalline shielding which predicts rearrangement propensity and structural volatility of individual particles under shear, identifying localized regions where the material's memory of its preparation is preserved. This contributes to understanding how local structure relates to dynamic response and memory in disordered systems.
Article
Materials Science, Multidisciplinary
Zilong Qiu, Annelies Malfliet, Muxing Guo, Bart Blanpain
Summary: A numerical sub-particle model is developed to study the dynamic behavior of nonmetallic inclusions attached to the gas/steel or slag/steel interface. The model simplifies the complex boundary conditions by using a sub-particle group to represent the quadrupolar parent inclusions and approximating the capillary interaction between them. The model accurately captures the anisotropic meniscus shape and interaction energy and force in different configurations.
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
(2022)
Article
Materials Science, Multidisciplinary
Luyun Zhang, Yiping Luo, Hongjuan Ren, Ying Wang, Zerui Gu
Summary: Based on the magnetic dipole theory, a micromechanical model of magnetorheological fluids (MRFs) containing spherical and ellipsoidal ferromagnetic particles was established. The shear stress of MRFs increases with the particle volume fraction and magnetic induction intensity. The new micromechanical model is more accurate than the traditional model with only spherical ferromagnetic particles.
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Pei Zhu, Feng Wang, Yanfen Ding, Shimin Zhang, Chong Gao, Peng Liu, Mingshu Yang
Summary: In this study, the phenomenon of double phase inversion was observed in Pickering emulsion when magnesium hydroxide nanosheets adsorbed with different amounts of SDS surfactants were used as stabilizers. The first inversion occurred due to increased hydrophobicity of the modified MH nanosheets, while the second inversion was a result of bilayer adsorption of SDS on MH nanosheets, making them hydrophilic again. These findings have significant implications for understanding the behavior of Pickering emulsions in the presence of surfactants and potential applications in reversible drilling fluids and oil extraction.
Article
Chemistry, Multidisciplinary
Thaddeus W. Golbek, Ryan A. Faase, Mette H. Rasmussen, Rik R. Tykwinski, Jeffrey M. Stryker, Simon Ivar Andersen, Joe E. Baio, Tobias Weidner
Summary: Petroleum asphaltenes are surface active compounds found in crude oils, with interactions with surfaces and interfaces impacting reservoir exploitation. This study used functionalized model asphaltenes on SAM surfaces to demonstrate different adsorption behaviors on hydrophobic and hydrophilic surfaces. Understanding pure and fractionated asphaltenes at the molecular level is crucial for predicting their varied surface interactions.
Article
Mechanics
F. Pelusi, M. Sega, J. Harting
Summary: Under the condition of partial surface wettability, thin liquid films can be destabilized by small perturbations and rupture into droplets. The rupture dynamics are dictated by the liquid-solid interaction and can be described using the thin film equation (TFE). The introduction of a secondary fluid can lead to a richer phenomenology but has not been investigated extensively. In this work, the authors study the rupture of liquid films with different heights immersed in a secondary fluid using a multi-component lattice Boltzmann approach.
Article
Multidisciplinary Sciences
Olivierj J. Ronsin, Jens Harting
Summary: In solution-processed thin films, the morphology resulting from liquid-liquid phase separation or polycrystallization during drying or subsequent processing steps has a strong influence on device performance. However, the process-structure relationship is poorly understood. A unified theoretical framework considering various physical phenomena is proposed to unravel the structure formation pathways. The behavior of the coupled model based on simple test cases is discussed and verified, and the framework is illustrated in investigating the morphology formation in drying films.
ADVANCED THEORY AND SIMULATIONS
(2022)
Article
Nanoscience & Nanotechnology
Olivier J. J. Ronsin, Jens Harting
Summary: This study uses a coupled phase-field-fluid mechanics framework to simulate the formation process of bulk-heterojunction (BHJ) morphology in organic solar cells. The simulation results match well with experimental results and can be used to optimize the cell's performance and develop physical design rules for ink formulation and processing conditions.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Physics, Multidisciplinary
G. C. Antunes, P. Malgaretti, J. Harting, S. Dietrich
Summary: Both numerical and analytical analysis have shown that a chemically patterned active pore can function as a micro- or nanopump for fluids, even if it is symmetric. This is due to a spontaneous symmetry breaking caused by the dominance of advection over diffusion in solute transport. It has been further demonstrated that a combination of geometrical and chemical inhomogeneities is required for pumping and controlling the flow rate. Under certain parameter values, the flow becomes unsteady and exhibits persistent oscillations with tunable frequency. Additionally, the flow generates convection rolls and promotes mixing in the low Reynolds number regime.
PHYSICAL REVIEW LETTERS
(2022)
Article
Mechanics
Othmane Aouane, Marcello Sega, Bastian Baeuerlein, Kerstin Avila, Jens Harting
Summary: This study numerically simulates the dynamics of rigid particle suspensions in wall-bounded laminar flow, including particle ordering and the formation of stable Segre-Silberberg annular regions. It is found that the formation of multiple annular regions is still not fully explained and the position of the secondary inner annular region shifts with the increase of channel length.
Review
Chemistry, Multidisciplinary
Mariya E. Ivanova, Ralf Peters, Martin Mueller, Stefan Haas, Martin Florian Seidler, Gerd Mutschke, Kerstin Eckert, Philipp Roese, Sonya Calnan, Rory Bagacki, Rutger Schlatmann, Cedric Grosselindemann, Laura-Alena Schaefer, Norbert H. Menzler, Andre Weber, Roel van de Krol, Feng Liang, Fatwa F. Abdi, Stefan Brendelberger, Nicole Neumann, Johannes Grobbel, Martin Roeb, Christian Sattler, Ines Duran, Benjamin Dietrich, M. E. Christoph Hofberger, Leonid Stoppel, Neele Uhlenbruck, Thomas Wetzel, David Rauner, Ante Hecimovic, Ursel Fantz, Nadiia Kulyk, Jens Harting, Olivier Guillon
Summary: Hydrogen produced from renewables will have a growing impact on global energy dynamics towards sustainability and carbon neutrality. However, the current share of green hydrogen is too low, and there is a rising demand for high-quality hydrogen. This highlights the need for economically viable hydrogen generation technologies. This article evaluates existing technologies for high-quality hydrogen production based on solar energy, considering their current development level, technical limitations, and future potential.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Andreas Baer, Paolo Malgaretti, Malte Kaspereit, Jens Harting, Ana-Suncana Smith
Summary: Accurately modeling the diffusion transport of nanoparticles across nanopores is a challenging problem due to the amplification of nanoscopic details and effective interactions at the pore wall. This study proposes a multiscale approach that combines molecular dynamics simulations and a stochastic model to determine the average diffusion constant. The model is applied to the diffusion of fullerenes in a toluene-filled slit nanopore and considers the influence of partial slip at the pore wall.
JOURNAL OF MOLECULAR LIQUIDS
(2022)
Article
Multidisciplinary Sciences
Zhiyuan Zhang, Alexander Sukhov, Jens Harting, Paolo Malgaretti, Daniel Ahmed
Summary: Researchers have successfully demonstrated the ability of microswarms to roll along virtual walls in the absence of physical boundaries. This breakthrough was achieved by employing a combination of magnetic and acoustic fields, overcoming the limitations of requiring physical boundaries for rolling movements.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Thomas Solymosi, Michael Geisselbrecht, Sophie Mayer, Michael Auer, Peter Leicht, Markus Terlinden, Paolo Malgaretti, Andreas Boesmann, Patrick Preuster, Jens Harting, Matthias Thommes, Nicolas Vogel, Peter Wasserscheid
Summary: In this study, the nucleation of gas bubbles in the catalyst pore structure is found to be an important rate-limiting step in reactions where gas is generated from liquid reactants. By inhibiting or enhancing nucleation, the reaction rate can be controlled, which has significant implications for reactions related to the future green hydrogen economy.
Article
Physics, Mathematical
D. Geyer, S. Ziegler, A. Sukhov, M. Hubert, A. -s. Smith, O. Aouane, P. Malgaretti, J. Harting
Summary: The performance of microswimmers, whether individually or collectively, is greatly influenced by the hydrodynamic coupling between their components and themselves. In this study, we conducted numerical simulations using the lattice Boltzmann method (LBM) to investigate the behavior of a single microswimmer and a pair of microswimmers. Our numerical approach involved the discretization of microswimmers using Lagrange polynomials, while the lattice Boltzmann method described the dynamics of the surrounding fluid. We observed the onset of collective effects and an overall velocity increment of clusters of swimmers in our data.
COMMUNICATIONS IN COMPUTATIONAL PHYSICS
(2023)
Article
Physics, Multidisciplinary
Paolo Malgaretti, Jens Harting
Summary: In the past decade, the Fick-Jacobs approximation has been used to study transport across constrictions. This paper reviews the derivation of the Fick-Jacobs equation with a focus on its linear response regime. It is found that for fore-aft symmetric channels, the flux of noninteracting systems can be fully captured by the linear response regime. A simple formula is derived for this case, which accurately captures the trends and can be used as a tool for experiment design and simulations. Furthermore, it is shown that higher-order corrections in the flux may arise for nonsymmetric channels.
Article
Chemistry, Physical
G. C. Antunes, P. Malgaretti, J. Harting
Summary: This study develops a semi-analytical model for self-diffusioosmotic transport in active pores. The authors investigate the spontaneous symmetry breaking in fore-aft symmetric pores and find that the pumping transition is controlled by three timescales. Introducing asymmetry to the pore reveals a second type of advection-enabled transition.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Physics, Fluids & Plasmas
Thomas Scheel, Qingguang Xie, Marcello Sega, Jens Harting
Summary: Liquid lens coalescence is a significant mechanism in various industrial and scientific applications. Massively parallel simulations have been conducted to investigate the numerical results of this mechanism in different dimensions and reveal the scaling laws for both the viscous and inertial regimes.
PHYSICAL REVIEW FLUIDS
(2023)
Article
Chemistry, Physical
Yazdan Rashidi, Othmane Aouane, Alexis Darras, Thomas John, Jens Harting, Christian Wagner, Steffen M. Recktenwald
Summary: Bifurcations and branches in the microcirculation have a significant impact on blood flow and the distribution of red blood cells. This study investigates the flow behavior of healthy and artificially hardened red blood cells in a bifurcating microfluidic T-junction. The results reveal distinct focusing profiles and the development of asymmetric cell-free layers in the daughter vessels for different types of red blood cells.
Article
Biology
Qi Zhou, Kerstin Schirrmann, Eleanor Doman, Qi Chen, Naval Singh, P. Ravi Selvaganapathy, Miguel O. Bernabeu, Oliver E. Jensen, Anne Juel, Igor L. Chernyavsky, Timm Kruger
Summary: Research has shown that the microhemodynamics of a vascular network, supported by its interconnected structure, plays a crucial role in blood flow patterns. Structural disorder in extravascular media can impact blood flow dynamics. Three main effects were observed in the study: the apparent viscosity of blood increases with structural disorder, the presence of red blood cells dynamically alters flow distribution, and moderate structural disorder can promote more uniform red blood cell distribution.
Article
Chemistry, Physical
Yiping Yin, Zhe Wang, Hua Zou
Summary: This study presents a novel method for preparing dimpled polymer-silica nanocomposite particles using interfacial swelling-based seeded polymerization. The optimized conditions allow for a relatively high percentage of dimpled particles to be achieved.
Article
Chemistry, Physical
Brenden D. Hoehn, Elizabeth A. Kellstedt, Marc A. Hillmyer
Summary: Porous materials with nanometer-scale pores have important applications as nanoporous membranes. In this study, ABA triblock copolymers were used as precursors to produce nanoporous polymeric membranes (NPMs) in thin film form by degrading the end blocks. Polycyclooctene (PCOE) NPMs with tunable pore sizes were successfully prepared using solvent casting technique. Oxygen plasma etching was employed to improve the surface porosity and hydrophilicity of the membranes. This study provides a straightforward method to produce tough NPMs with high porosity and hydrophilic surface properties.
Article
Chemistry, Physical
Vladislav S. Petrovskii, Stepan I. Zholudev, Igor I. Potemkin
Summary: This article investigates the behavior of linear and ring polypeptide chains in aqueous solution and explores the properties of the complexes formed by these chains with oppositely charged surfactants. The results demonstrate that the complexes of linear supercharged unfolded polypeptides and the corresponding surfactants exhibit impressive adhesive properties.
Article
Chemistry, Physical
Merve Cevik, Serkan Dikici
Summary: Cardiovascular diseases are a leading cause of death globally, and vascular grafts are a promising treatment option. This study focuses on tissue-engineered vascular grafts (TEVGs) using decellularized parsley stems as a potential biomaterial. The decellularized parsley stems showed suitable properties for TEVGs, providing a suitable environment for human endothelial cells to form a pseudo endothelium. This study showcases the potential of using parsley stems for TEVGs.
Article
Chemistry, Physical
Gustavo A. Vasquez-Montoya, Tadej Emersic, Noe Atzin, Antonio Tavera-Vazquez, Ali Mozaffari, Rui Zhang, Orlando Guzman, Alexey Snezhko, Paul F. Nealey, Juan J. de Pablo
Summary: The optical properties of liquid crystals are typically controlled by electric fields. In this study, we investigate the effects of microfluidic flows and acoustic fields on the molecular orientation and optical response of nematic liquid crystals. We identify several previously unknown structures and explain them through calculations and simulations. These findings hold promise for the development of new systems combining sound, flow, and confinement.
Article
Chemistry, Physical
Xinjun Wu, Xin Guan, Shushu Chen, Jiangpeng Jia, Chongyi Chen, Jiawei Zhang, Chuanzhuang Zhao
Summary: This research presents a novel shape memory hydrogel with a remodelable permanent shape and programmable cold-induced shape recovery behavior. The hydrogel is prepared using specific treatment methods to achieve shape fixation by heating and shape recovery by cooling. Additionally, deformable devices can be obtained by assembling hydrogel blocks with different concentrations.
Article
Chemistry, Physical
Rebecca Hengsbach, Gerhard Fink, Ulrich Simon
Summary: This study examines the properties of DNA functionalized pNipmam microgels and pure pNipmam microgels at different concentrations of sodium chloride and in PBS solutions using temperature dependent H-1-NMR measurements. The results show that DNA modification affects the volume phase transition temperature and the addition of salt and PBS further enhances this effect.
Article
Chemistry, Physical
Ningyi Li, Junhong Li, Lijingting Qing, Shicheng Ma, Yao Li, Baohui Li
Summary: This paper investigates the self-assembly behavior of colloids with competing interactions under spherical confinement and finds that different ordered structures can be formed under different sized spherical confinements. Moreover, more perforated structures are formed in smaller spheres.
