Soft Matter最新文献_第8页

Spontaneous generation of angular momentum in chiral active crystals

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-26 DOI: 10.1039/D4SM01426J

Umberto Marini Bettolo Marconi and Lorenzo Caprini

{"title":"Spontaneous generation of angular momentum in chiral active crystals","authors":"Umberto Marini Bettolo Marconi and Lorenzo Caprini","doi":"10.1039/D4SM01426J","DOIUrl":"10.1039/D4SM01426J","url":null,"abstract":"We study a two-dimensional chiral active crystal composed of underdamped chiral active particles. These particles, characterized by intrinsic handedness and persistence, interact via linear forces derived from harmonic potentials. Chirality plays a pivotal role in shaping the system's behavior: it reduces displacement and velocity fluctuations while inducing cross-spatial correlations among different Cartesian components of velocity. These features distinguish chiral crystals from their non-chiral counterparts, leading to the emergence of net angular momentum, as predicted analytically. This angular momentum, driven by the torque generated by the chiral active force, exhibits a non-monotonic dependence on the degree of chirality. Additionally, it contributes to the entropy production rate, as revealed through a path-integral analysis. We investigate the dynamic properties of the crystal in both Fourier and real space. Chirality induces a non-dispersive peak in the displacement spectrum, which underlies the generation of angular momentum and oscillations in time-dependent autocorrelation functions or mean-square displacement, all of which are analytically predicted.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 14","pages":" 2586-2606"},"PeriodicalIF":2.9,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603257","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

The role of phosphate in silk fibroin self-assembly: a Hofmeister study†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-26 DOI: 10.1039/D4SM01198H

Caleb Wigham, Vrushali Varude, Henry O’Donnell and R. Helen Zha

{"title":"The role of phosphate in silk fibroin self-assembly: a Hofmeister study†","authors":"Caleb Wigham, Vrushali Varude, Henry O’Donnell and R. Helen Zha","doi":"10.1039/D4SM01198H","DOIUrl":"10.1039/D4SM01198H","url":null,"abstract":"Silk fibroin is the primary protein component of the threads of Bombyx mori silkworm cocoons. Previous work has demonstrated that silk fibroin can self-assemble at solid–liquid interfaces to form dense, nanothin coatings that grow continuously from a substrate surface when exposed to potassium phosphate, a kosmotropic salt. Herein, the role of potassium phosphate in promoting silk fibroin self-assembly in solution and on surfaces is studied and compared to other salts in the Hofmeister series. Results show that strong kosmotropes, such as ammonium sulfate and potassium phosphate, promote a bimodal distribution of assembled species in solution that is indicative of a nucleation-growth mechanism. Interestingly, silk fibroin assemblies formed by potassium phosphate contain the highest β-sheet content, suggesting that phosphate-specific interactions play a role in silk fibroin self-assembly. In the presence of kosmotropic salts, silk fibroin nanoaggregates continuously accumulate at solid–liquid interfaces with varying early- and late-stage adsorption rates. Interfacial coatings formed in the presence of potassium phosphate are smooth, dense, and completely cover the underlying substrate without evidence of large-scale aggregation, whereas other kosmotropes generate rough, heterogeneous coatings. These studies thus decouple the kosmotropic effects of phosphate (via disruption of the protein hydration shell) from ion-specific behavior in driving silk fibroin self-assembly.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2461-2470"},"PeriodicalIF":2.9,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sm/d4sm01198h?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143539617","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

Microstructural evolution in drying colloidal films driven by evaporation and sedimentation: lattice Boltzmann simulation and a mathematical model†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01498G

Jinseong Yun, Byoungjin Chun and Hyun Wook Jung

{"title":"Microstructural evolution in drying colloidal films driven by evaporation and sedimentation: lattice Boltzmann simulation and a mathematical model†","authors":"Jinseong Yun, Byoungjin Chun and Hyun Wook Jung","doi":"10.1039/D4SM01498G","DOIUrl":"10.1039/D4SM01498G","url":null,"abstract":"Understanding the temporal evolution of particle distribution during the drying of colloidal films is essential for advancing the design and optimization of film properties. This study investigates the dynamics of colloidal particles during vertical drying using the lattice Boltzmann method. Simulation results reveal that the particle distribution during drying and the resulting film microstructure are governed by two key dimensionless numbers: the drying Péclet number (Pe) and the sedimentation Péclet number (Pesed). When the evaporation rate exceeds the sedimentation rate (Pe ≫ Pesed), particles accumulate near the air–liquid interface, ultimately forming a colloidal crystal in the top layer. Conversely, when sedimentation dominates (Pe ≪ Pesed), similar accumulation and crystallization occur near the bottom substrate. These findings underscore the critical influence of drying and sedimentation dynamics on the final microstructural quality of colloidal films. To complement the simulation results, a one-dimensional mathematical drying model is developed, incorporating hydrodynamic hindrance and collective diffusivity effects resulting from particle accumulation. This model demonstrates quantitative agreement with simulation results across a wide range of Pe and Pesed. Using this model, new drying regime maps are constructed in the Pe and Pesed spaces, delineating distinct regions dominated by evaporation, diffusion, or sedimentation.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2430-2444"},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536163","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

Adhesion study at the interface of a PDMS-elastomer and borosilicate glass-slide: effect of modulus and thickness of the elastomer

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01249F

Susheel Kumar, Chiranjit Majhi, Krishnacharya Khare and Manjesh K. Singh

{"title":"Adhesion study at the interface of a PDMS-elastomer and borosilicate glass-slide: effect of modulus and thickness of the elastomer","authors":"Susheel Kumar, Chiranjit Majhi, Krishnacharya Khare and Manjesh K. Singh","doi":"10.1039/D4SM01249F","DOIUrl":"10.1039/D4SM01249F","url":null,"abstract":"Adhesion control at the interface of two surfaces is crucial in many applications. Examples are the design of micro and nanodevices such as microfluidic devices, biochips, and electronic sensors. Adhesion at the interface of two materials can be controlled by various methods, such as chemical treatment on the surface of the materials, modification of the surface texture of the materials, and change of the mechanical properties of the materials. The main idea of this study is to control the adhesion by changing the mechanical properties (modulus) of the polydimethylsiloxane (PDMS) elastomer. We vary the modulus of the PDMS elastomer by changing mixing ratio (w/w) of the silicone elastomer base and its curing agent (SylgardTM 184, Dow Corning). Our study also includes the effect of the thickness of the PDMS elastomer sheet on its adhesion behavior. Adhesion measurements at the interface of the borosilicate glass slide and different PDMS elastomer specimens were performed using a wedge test. This method inserts a glass coverslip at the interface to create a wedge. We observe a significant decrease in the work of adhesion and an increase in equilibrium crack length with an increase in elastic-modulus and thickness of the PDMS elastomer samples. We present and discuss the effect of modulus and specimen-thickness on the adhesion behavior of the PDMS elastomer against a glass slide.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2493-2501"},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565590","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

Wet spinning of sodium carboxymethyl cellulose-sodium caseinate hydrogel fibres: relationship between rheology and spinnability.

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/d4sm00705k

Lathika Vaniyan, Pallab Kumar Borah, Galina E Pavlovskaya, Nick Terrill, Joshua E S J Reid, Michael Boehm, Philippe Prochasson, Reed A Nicholson, Stefan Baier, Gleb E Yakubov

{"title":"Wet spinning of sodium carboxymethyl cellulose-sodium caseinate hydrogel fibres: relationship between rheology and spinnability.","authors":"Lathika Vaniyan, Pallab Kumar Borah, Galina E Pavlovskaya, Nick Terrill, Joshua E S J Reid, Michael Boehm, Philippe Prochasson, Reed A Nicholson, Stefan Baier, Gleb E Yakubov","doi":"10.1039/d4sm00705k","DOIUrl":"10.1039/d4sm00705k","url":null,"abstract":"Mimicking the fibrous structures of meat is a significant challenge as natural plant protein assemblies lack the fibrous organisation ubiquitous in mammalian muscle tissues. In this work, wet-spun hydrogel fibres resembling the anisotropic fibrous microstructure of meat are fabricated using carboxymethyl cellulose as a model polysaccharide and sodium caseinate as a model protein which are crosslinked using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC). Hydrogels and spun fibres were characterised using a combination of rheology (shear, oscillatory, and extensional), microscopy (light, polarised, and fluorescence), rheo-NMR, and X-ray diffraction. Examination of structuring behaviour under shear uncovered a relationship between enhanced biopolymer orientation along the fibre axis and a viscoelastic time-dependent ageing window for optimal hydrogel spinnability. This study provides novel rheological and structural insights into mechanisms of protein-polysaccharide assembly that may prove instrumental for development of tuneable fibres for applications in plant-based foods, tissue engineering, and biomaterials.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" ","pages":""},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11852227/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143490185","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

Taming the diffusiophoretic convective instability in colloidal suspensions

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01432D

Stefano Castellini, Carmine Anzivino, Carlo Marietti, Marina Carpineti, Alessio Zaccone and Alberto Vailati

{"title":"Taming the diffusiophoretic convective instability in colloidal suspensions","authors":"Stefano Castellini, Carmine Anzivino, Carlo Marietti, Marina Carpineti, Alessio Zaccone and Alberto Vailati","doi":"10.1039/D4SM01432D","DOIUrl":"10.1039/D4SM01432D","url":null,"abstract":"A suspension of Brownian colloidal particles stabilised against aggregation is expected to be stable against convection when its density decreases monotonically with height. Surprisingly, a recent experimental investigation has shown that when colloidal particles are dispersed uniformly in a solvent with a stabilising stratification of a molecular solute, the system develops a convective instability under generic conditions [Anzivino et al., J. Phys. Chem. Lett., 2024, 15, 9030]. This instability arises because the solute concentration gradient induces an upward diffusiophoretic motion of the colloidal particles, triggering a diffusiophoretic convective instability (DCI). In this work, we investigate the stability of a colloidal suspension against convection in the presence of a stable density stratification of the sample, under different initial conditions. In particular, we study the condition where both the colloid and the molecular solute are initially localized in the lower half of the sample prior to merging with the upper half made of pure water. This is unlike the previously studied setup where the colloid was initially present also in the upper half, suspended in water. We show that only when the concentration of glycerol exceeds a fairly large threshold value of approximately 0.3 w/w the system develops the convective instability. Hence, this new setup offers the possibility to tame DCI by changing the initial conditions. We model the experimental results by numerically solving the nonlinear double diffusion equations in the presence of a diffusiophoretic coupling to determine the time evolution of the base state of the system. The theoretical analysis allows us to elucidate the physical reason for the existence of the threshold value of the glycerol concentration and to establish that the interactions between the colloidal particles do not play a significant role in the DCI.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 14","pages":" 2578-2585"},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2025/sm/d4sm01432d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143565496","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

On the Ostwald ripening of crystalline and amorphous nanoparticles 晶体和无定形纳米粒子的奥斯特瓦尔德熟化。

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01544D

Manja Annette Behrens, Alexandra Franzén, Sara Carlert, Urban Skantze, Lennart Lindfors and Ulf Olsson

引用次数: 0

Quantitative rationalization of the unexpectedly moderate water wettability of poly(vinyl alcohol) surfaces: thermodynamic evaluation and prediction of surface hydrogen bonding†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-25 DOI: 10.1039/D4SM01524J

Zhuohuan Guo, Zhuoyuan Ma and Dayang Wang

{"title":"Quantitative rationalization of the unexpectedly moderate water wettability of poly(vinyl alcohol) surfaces: thermodynamic evaluation and prediction of surface hydrogen bonding†","authors":"Zhuohuan Guo, Zhuoyuan Ma and Dayang Wang","doi":"10.1039/D4SM01524J","DOIUrl":"10.1039/D4SM01524J","url":null,"abstract":"In this work, a series of poly(vinyl alcohol) (PVA) films with defined but varied water wettability was prepared by curing as-prepared PVA films at systematically adjusted temperatures. The polar components of surface energy (γs,p) of the resulting PVA films were calculated and correlated with the molecular configurations of their surface OH groups—free OH (OHf), trans-hydrogen bonded OH (OHt), and gauche-hydrogen bonded OH groups (OHg)—with the aid of attenuated total reflectance Fourier transform infrared spectroscopy. By decomposing the γs,p values of the PVA films as a sum of the contributions from OHf, OHt, and OHg groups, the intrinsic γs,p components of <img> and <img> were calculated to be 8.0 mN m−1 and 9.8 mN m−1, respectively, which were substantially smaller than that of <img>. This provided a thermodynamic foundation not only to rationalize the unexpectedly moderated surface hydrophilicity of PVA films but also to quantitatively predict the fHB component of hydrogen-bonded OH groups on their surfaces according to their water wettability.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 13","pages":" 2548-2557"},"PeriodicalIF":2.9,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143603256","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

A torrent intercepts the ionic flow in a polyelectrolyte solution†

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-24 DOI: 10.1039/D4SM01381F

Kaito Watanabe, Sayaka Naya, Yoshifumi Yamagata, Keisuke Miyamoto, Mika Kawai and Tetsu Mitsumata

引用次数: 0

Reinforcement learning selects multimodal locomotion strategies for bioinspired microswimmers

IF 2.9 3区化学

Soft Matter Pub Date : 2025-02-24 DOI: 10.1039/D4SM01274G

Yangzhe Liu, Zhao Wang and Alan C. H. Tsang

{"title":"Reinforcement learning selects multimodal locomotion strategies for bioinspired microswimmers","authors":"Yangzhe Liu, Zhao Wang and Alan C. H. Tsang","doi":"10.1039/D4SM01274G","DOIUrl":"10.1039/D4SM01274G","url":null,"abstract":"Natural microswimmers exhibit multimodal locomotion strategies to achieve versatile navigation tasks such as finding nutrient sources, avoiding danger and migrating to new habitats. These multimodal locomotion strategies typically involve complex coordination of cell actuators (i.e., flagella) to generate translation, rotation and combined motions. Yet, it is generally difficult to establish a simple relationship between actuation and locomotion strategies due to the complex hydrodynamic coupling between the swimmer and the surrounding fluid. While many bioinspired microswimmers have been engendered, it remains challenging for these artificial swimmers to generate effective locomotion strategies for different functional tasks similar to their biological counterparts. Here, we explore a reinforcement learning (RL) method to enable a bioinspired microswimmer to select locomotion strategies based on different functional tasks. We illustrate this approach using a bioinspired model swimmer derived from Chlamydomonas reinhardtii, which consists of a body sphere and two flagella spheres. We first demonstrate that this RL-powered bioinspired swimmer can select effective locomotion strategies that maximize displacement or minimize energy input by setting corresponding learning goals. We further illustrate how RL can enable the bioinspired swimmer to achieve multi-directional navigation via multimodal locomotion strategies that coordinately switch between forward and steering gaits. Our approach opens a new avenue to designing bioinspired microswimmers with multimodal locomotion capabilities.","PeriodicalId":103,"journal":{"name":"Soft Matter","volume":" 12","pages":" 2363-2373"},"PeriodicalIF":2.9,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143536167","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