Soft Matter最新文献_第5页

Capillary-induced adhesive contact dynamics determines dissipation and flow structure in wetted hydrogel packings. 毛细管诱导的黏着接触动力学决定了湿凝胶填料的耗散和流动结构。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-17 DOI: 10.1039/d5sm00221d

Zohreh Farmani, Jing Wang, Ralf Stannarius, Joshua A Dijksman

{"title":"Capillary-induced adhesive contact dynamics determines dissipation and flow structure in wetted hydrogel packings.","authors":"Zohreh Farmani, Jing Wang, Ralf Stannarius, Joshua A Dijksman","doi":"10.1039/d5sm00221d","DOIUrl":"https://doi.org/10.1039/d5sm00221d","url":null,"abstract":"The bulk response of a granular material is strongly influenced by particle and contact properties, such as friction coefficients, particle softness, lubrication on the contact scale and adhesion between particles. This study explores the bulk flow of wetted hydrogel particles, which are soft but also weakly adhesive due to capillary bridges. This simplified granular material with minimal contact friction reveals key insights in the role of capillary stresses on the macroscopic flow. At the micro-scale, we demonstrate a direct correlation between relative humidity (RH) and liquid bridge size between two wetted hydrogel spheres, with an average rupture distance increasing with humidity. On the macro scale, the wetted hydrogel sphere packings show remarkable flow dissipation and flow behavior in the split-bottom shear cell. We retrieve flow fields of the hydrogel packing with magnetic resonance imaging and measure flow resistance with a rheometric technique. The shear bands for the adhesive hydrogels are much narrower than for dry grain flows. The change in flow resistance due to a change in filling height can be interpreted with a minimization argument, indicating that the flow dissipation is set entirely by the capillary bridge stress: the capillary stress at all filling heights dominates the gravitational stress. We confirm this view by exposing the flowing packing to an external pressure. Beyond a confining stress of 250 Pa, the shear bands become significantly thinner, approaching some plateau at 360 Pa. This underscores the importance of understanding micro-scale interactions in controlling macroscopic hydrogel particle packing behavior.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144309227","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Micromechanical modelling of cellulose hydrogel composites based on coarse-grained molecular dynamics. 基于粗粒度分子动力学的纤维素水凝胶复合材料微观力学建模。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-17 DOI: 10.1039/d4sm01488j

Mauricio R Bonilla, Sridhar K Kannam, Matthew T Downton, Monika S Doblin, Antony Bacic, Michael J Gidley, Jason R Stokes

{"title":"Micromechanical modelling of cellulose hydrogel composites based on coarse-grained molecular dynamics.","authors":"Mauricio R Bonilla, Sridhar K Kannam, Matthew T Downton, Monika S Doblin, Antony Bacic, Michael J Gidley, Jason R Stokes","doi":"10.1039/d4sm01488j","DOIUrl":"https://doi.org/10.1039/d4sm01488j","url":null,"abstract":"The mechanical response and structure of cellulose hydrogel composites (CHCs) are modelled as cellulose microfibrils using a bead-spring coarse-graining approach. Our results demonstrate that varying the adhesive contact energy between the flexible chains, as well as the number of contacts and structural anisotropy, significantly impacts the mechanical response of the network structure under tensile forces. Specifically, decreasing the contact energy and increasing its range is sufficient to increase the network's extensibility while decreasing its overall modulus. This key finding aligns qualitatively with experiments where the inclusion of polysaccharides in bacterial cellulose-based CHCs had an analogous effect. We hypothesise that polysaccharides, including hemicelluloses, facilitate alignment under strain by increasing the range (\"softening\") of the contact forces between microfibrils. Conversely, their absence results in \"hard\" contacts between microfibrils that are more energetic and can only act over short distances. In contrast to finite element models for CHCs, this coarse-grained approach incorporates non-permanent contacts between flexible microfibrils that permits structural rearrangement of the network in response to deformation, whereby controlling the density and proportion of long- and short- range contact forces suffice to qualitatively describe experiments. Controlling interactions between microfibrils thus provides a lever for designing CHCs with specific mechanical properties for various applications. Additionally, we suggest that plants naturally tune these variables in plant cell development to balance wall rigidity and extensibility.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144309228","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Correction: Evolution of shear zones in granular packings under pressure 修正：压力下颗粒填料中剪切带的演化。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-13 DOI: 10.1039/D5SM90107C

Mahnoush Madani, Maniya Maleki, János Török and M. Reza Shaebani

引用次数: 0

Fluctuation induced network patterns in active matter with spatially correlated noise. 具有空间相关噪声的活性物质波动诱导的网络模式。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-13 DOI: 10.1039/d5sm00245a

Sebastian Fehlinger, Kai Cui, Arooj Sajjad, Heinz Koeppl, Benno Liebchen

{"title":"Fluctuation induced network patterns in active matter with spatially correlated noise.","authors":"Sebastian Fehlinger, Kai Cui, Arooj Sajjad, Heinz Koeppl, Benno Liebchen","doi":"10.1039/d5sm00245a","DOIUrl":"https://doi.org/10.1039/d5sm00245a","url":null,"abstract":"Fluctuations play a central role in many fields of physics, from quantum electrodynamics to statistical mechanics. In active matter physics, most models focus on thermal fluctuations due to a surrounding solvent. An alternative but much less explored noise source can occur due to fluctuating external fields, which typically feature certain spatial correlations. In this work, we introduce a minimal model to explore the influence of spatially correlated but temporally uncorrelated noise on the collective behaviour of active particles. We find that specifically in chiral active particles such fluctuations induce the formation of network patterns, which neither occur for spatially (uncorrelated) thermal noise, nor in the complete absence of fluctuations. These networks show (i) a percolated structure, (ii) local alignment of the contained particles, but no global alignment, and (iii) hardly coarsen. We perform a topological data analysis to systematically characterize the topology of the network patterns. Our work serves as a starting point to explore the role of spatially correlated fluctuations and presents a route towards noise-induced phenomena in active matter.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144289363","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Low-profile folding mechanism for multi-DoF feedback control. 低轮廓折叠机构多自由度反馈控制。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-13 DOI: 10.1039/d5sm00143a

Hwayeong Jeong, Jung Kim, Jamie Paik

{"title":"Low-profile folding mechanism for multi-DoF feedback control.","authors":"Hwayeong Jeong, Jung Kim, Jamie Paik","doi":"10.1039/d5sm00143a","DOIUrl":"https://doi.org/10.1039/d5sm00143a","url":null,"abstract":"Soft structures gain their adaptability from a high number of distributed degrees of freedom (DoF). Integrating reconfigurable robotic systems into these soft structures enables efficient transmission of forces and torques, supporting a wide range of tasks. However, implementing actuation, sensing, and transmission components remains challenging, particularly in optimizing their spatial distribution to achieve effective control over the target structure. In this study, we present an embeddable pneumatic system featuring ultra-thin actuators, with integrable sensors and modular transmissions. The system's ultra-thin profile enables seamless and space-efficient integration onto various surfaces, while its modular design enables flexible reconfiguration to suit different mechanical and control needs. The rolling diaphragm mechanism reduces friction and stress on the joints which are more prone to occur in flat structures. The proposed diaphragm has an aspect ratio of approximately 10 (15 mm 1.4 mm cross-section) and achieves a stroke length up to five times its thickness, extendable through modular connection. An optical sensor module is also introduced to provide precise, low-profile feedback without affecting the mechanical characteristics or flatness of the overall system. We demonstrate the control of folding sequence and angle through feedback control, using compactly embedded components within an origami-inspired surface. This approach leverages the geometric principles of folding to enable complex and reconfigurable structures. The proposed integrable actuator, transmission, and sensor module provides a scalable and customizable foundation for developing large-scale robotic systems with intricate geometries and distributed control, supporting seamless deployment and adaptability.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144281752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Mechanics control the proliferation of diatoms entrapped in hydrogels† 力学控制着水凝胶中硅藻的增殖。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-11 DOI: 10.1039/D5SM00391A

Rani Boons, Dominic Gerber, Robert W. Style, Anouk Droux, Tanja Zimmermann, Gustav Nyström, Gilberto Siqueira and André R. Studart

{"title":"Mechanics control the proliferation of diatoms entrapped in hydrogels†","authors":"Rani Boons, Dominic Gerber, Robert W. Style, Anouk Droux, Tanja Zimmermann, Gustav Nyström, Gilberto Siqueira and André R. Studart","doi":"10.1039/D5SM00391A","DOIUrl":"10.1039/D5SM00391A","url":null,"abstract":"The proliferation of microorganisms in hydrogels is crucial for the design of engineered living materials and biotechnological processes, and may provide insights into cellular growth in aquatic environments. While the mechanical properties of the gel have been shown to affect the division of entrapped cells, research is still needed to understand the impact and the origin of mechanical forces controlling the growth of microorganisms inside hydrogels. Using diatoms as model microorganisms, we investigate the viability, time to division and growth dynamics of cells entrapped in agar hydrogels with tuneable mechanical properties. Cell culture experiments, confocal optical microscopy and particle tracking velocimetry are performed to uncover the role of stress relaxation and residual stresses in the gel and how these affect diatom proliferation. Our experiments reveal that the interplay between the internal pressure of the dividing cell and the mechanical response of the hydrogel control the proliferation behaviour of the entrapped diatoms. By providing quantitative guidelines for the selection of hydrogels for the entrapment and growth of microorganisms, this study offers new insights on the design of living materials for established and emerging biotechnologies.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 26","pages":" 5359-5370"},"PeriodicalIF":2.9,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12153043/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264859","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Self consistent field theory of isotropic-nematic interfaces and disclinations in a semiflexible molecule nematic. 半柔性分子向列中各向同性界面和斜向的自洽场论。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-11 DOI: 10.1039/d5sm00278h

Longyu Qing, Jorge Viñals

{"title":"Self consistent field theory of isotropic-nematic interfaces and disclinations in a semiflexible molecule nematic.","authors":"Longyu Qing, Jorge Viñals","doi":"10.1039/d5sm00278h","DOIUrl":"https://doi.org/10.1039/d5sm00278h","url":null,"abstract":"A Self Consistent Field Theory description of equilibrium, but non uniform, configurations adopted by semi flexible liquid crystal molecules is presented. Two cases are considered, isotropic-nematic phase boundaries, and topological defects in the nematic phase (disclinations). Nematogens are modeled by worm-like chains, with microscopic interaction potential of the Maier-Saupe (MS) type, with an added isotropic excluded volume contribution. The thermodynamic fields obtained by numerical minimization of the free energy are the molecular density and the nematic tensor order parameter. Interfaces with both homeotropic and planar alignment are studied, as well as biaxiality and anisotropy around ±1/2 disclinations. The effects induced by fluid compressibility, interaction strength, and elastic anisotropy that follows from chain flexibility on both types of nonuniform configurations are discussed. Defect core sizes decrease as the system becomes less compressible, eventually reaching a constant value in the incompressible limit. The core size is influenced by the nematic interaction strength u2 and chain persistence length lp, decreasing as the order increases in the nematic region through manipulation of lp and u2. In incompressible limit and for fixed far field nematic order, the core size is seen to be on order of chain contour length for rigid chains, and it decreases as the chains become more flexible.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144264904","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Surface buckling enabled soft clutch† 表面屈曲使软离合器。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-10 DOI: 10.1039/D5SM00299K

Zichao Dai, Tong Wang, Wei Wu, Junpeng Ma, Hang Xiao, Xi Chen and Liangliang Zhu

引用次数: 0

Comparative molecular dynamics simulation studies of simple and polymerized ionic liquids† 简单和聚合离子液体的分子动力学模拟比较研究。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-09 DOI: 10.1039/D5SM00307E

Arshid Ahmad, Robin Köster, Sebastian Kloth and Michael Vogel

{"title":"Comparative molecular dynamics simulation studies of simple and polymerized ionic liquids†","authors":"Arshid Ahmad, Robin Köster, Sebastian Kloth and Michael Vogel","doi":"10.1039/D5SM00307E","DOIUrl":"10.1039/D5SM00307E","url":null,"abstract":"We perform molecular dynamics simulations to compare the structures and dynamics of a simple and a polymerized ionic liquid. The latter comprises [BF4] anions and [(CH2)6–C3H3N2]25 cations and, hence, the charged imidazolium rings are, unlike in most previous studies, embedded in the polymer backbone rather than in side chains. It is found that cation polymerization weakly affects the local structure but leads to a strong slowdown and an enhanced heterogeneity of the dynamics. Despite strongly different diffusion coefficients of the anions and polymerized cations, reflecting single ion conductor behavior, the structural relaxation of the anions remains coupled to the segmental polymer motion. A comparison with literature results indicates that polymerized cations with embedded and pendant imidazolium rings exhibit different anion association and cause different anion transport mechanisms, with prevailing diffusive and hopping motions, respectively. In addition, we observe that the Rouse model reasonably well describes the polymer dynamics in our case of charged chains strongly interacting with counterions. Specifically, it captures the static amplitudes and time constants of the lower Rouse modes, while there are strong deviations from the model predictions for the higher Rouse modes, which are associated with smaller length scales and sensitive to structural and dynamical heterogeneity related to polycation–anion association.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 26","pages":" 5231-5241"},"PeriodicalIF":2.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144245322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Colloidoscope: detecting dense colloids in 3D with deep learning. 胶体镜：利用深度学习技术检测三维致密胶体。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-06-09 DOI: 10.1039/d4sm01307g

Abdelwahab Kawafi, Lars Kürten, Levke Ortlieb, Yushi Yang, Abraham Mauleon Amieva, James Hallett, C Patrick Royall

{"title":"Colloidoscope: detecting dense colloids in 3D with deep learning.","authors":"Abdelwahab Kawafi, Lars Kürten, Levke Ortlieb, Yushi Yang, Abraham Mauleon Amieva, James Hallett, C Patrick Royall","doi":"10.1039/d4sm01307g","DOIUrl":"https://doi.org/10.1039/d4sm01307g","url":null,"abstract":"Colloidoscope is a deep learning pipeline employing a 3D residual U-net architecture, designed to enhance the tracking of dense colloidal suspensions through confocal microscopy. This methodology uses a simulated training dataset that reflects a wide array of real-world imaging conditions, specifically targeting high colloid volume fraction and low-contrast scenarios where traditional detection methods struggle. Central to our approach is the use of experimental signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), and point-spread-functions (PSFs) to accurately quantify and simulate the experimental data. Our findings reveal that Colloidoscope achieves superior recall in particle detection (it finds more particles) compared to conventional methods. Simultaneously, high precision is maintained (high fraction of true positives). The model demonstrates a notable robustness to photobleached samples, thereby prolonging the imaging time and number of frames that may be acquired. Furthermore, Colloidoscope maintains small scale resolution sufficient to classify local structural motifs. Evaluated across both simulated and experimental datasets, Colloidoscope brings the advancements in computer vision offered by deep learning to particle tracking at high volume fractions. We offer a promising tool for researchers in the soft matter community. This model is deployed and available to use pretrained at https://github.com/wahabk/colloidoscope.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144245347","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0