Download or read book Confined Flow of Attractive Colloidal Suspensions written by Rahul Pandey and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Attractive particulate fluids flowing through complex confined geometries are frequently used in technological applications. While the flow properties of hard-sphere suspensions in micro-scale geometries have been studied extensively, the effects of interparticle attractions and particle size dispersity on the confined flow properties of particulate suspensions are not well understood. We used confocal microscopy, particle tracking, and bulk rheology to study the confined structure, dynamics, and flow properties of colloid-polymer mixtures, which serve as simple models of attractive particulate suspensions. We employed poly(methyl-methacrylate) spheres that were suspended in a refractive-index and density- matched solvent, and induced a controlled short-range depletion attraction between particles by adding non-absorbing linear polystyrene. First, we investigated the effects of particle size dispersity on confinement-induced solidification of colloid-polymer mixtures. We formulated mixtures of polymer and bidispersed colloids with particle size ratio aS/aL ≈ 0.49 at a constant total volume fraction fT and measured the dynamics of the large particles as a function of the volume fraction of large particles. The dynamics of large particles became slower as the volume fraction of large particles r=fL/fT was decreased or the confinement thickness was decreased, indicating increasingly solid-like behavior. Second, we investigated the effects of variation in particle size dispersity r on the rheology and microstructure of mixtures of polymer and bidispersed colloids. Significant changes in rheology and microstructure were observed only at high volume fractions of large particles. By contrast, dense suspensions fT = 0.40 were strong gels at all concentration of large particles and exhibited only modest rheological and microstructural changes. Finally, we investigated the effects of variation in interparticle attractions on the microchannel flow of colloid-polymer mixtures. In suspensions with weak interparticle attractions, the number density of particles increased downstream in the channel due to shear-induced migration and consolidation by compression. In suspensions with stronger interparticle attractions, an interconnected network of particles suppressed these mechanisms and prevented the increase in density downstream. Together, our results indicate that the confined structure, dynamics, and flow properties of attractive colloidal suspensions can be controllably tuned from fluid-like to solid-like by varying the interparticle attractions and the particle size dispersity.
Download or read book Non equilibrium Dynamics of Confined Colloidal Suspensions in Shear flow written by Sascha Gerloff and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Non equilibrium Dynamics and Feedback Control of Strongly Confined Colloidal Suspensions in a Planar Shear Flow written by Tarlan Azad Vezirov and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloidal Suspension Rheology written by Jan Mewis and published by Cambridge University Press. This book was released on 2012 with total page 417 pages. Available in PDF, EPUB and Kindle. Book excerpt: Presented in an accessible and introductory manner, this is the first book devoted to the comprehensive study of colloidal suspensions.
Download or read book Theory and Applications of Colloidal Suspension Rheology written by Norman J. Wagner and published by Cambridge University Press. This book was released on 2021-04-15 with total page 437 pages. Available in PDF, EPUB and Kindle. Book excerpt: Essential text on the practical application and theory of colloidal suspension rheology, written by an international coalition of experts.
Download or read book Structure and Diffusion in Dense Confined Colloidal Suspensions written by Bianxiao Cui and published by . This book was released on 2002 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Shear Behavior and Microstructures of Confined Colloidal Suspensions written by John Eric Hug and published by . This book was released on 1995 with total page 662 pages. Available in PDF, EPUB and Kindle. Book excerpt: Rheological properties and microstructures of concentrated charge-stabilized suspensions confined to gap sizes on the order of a few particle diameters are investigated by molecular dynamics computer simulations. Suspensions of uniform spheres at volume fractions ranging from 0.28 to 0.53 covering the crystalline phase are studied. The suspensions are modeled as spheres interacting via a repulsive short-ranged electrostatic potential. Stress versus shear rate behavior is examined as a function of particle volume fraction, gap size, and shear history. Microstructures for systems at equilibrium and under shear are investigated by direct observation of particle configurations and by scattering patterns generated from structure factor calculations. The observed shear behavior and microstructures compare favorably with experimental shear studies of bulk colloidal suspensions. The shear response and stresses marking rheological transitions scale on the equilibrium modulus in a universal manner. Small changes in gap size result in significant differences in the equilibrium properties which in turn can affect the observed rheological response. Gap size also plays an important role at shear rates where catastrophic shear thinning and shear thickening occur. Qualitative differences in shear behavior between experiments and simulations are observed at high shear rates suggesting that particle interactions dominate the shear behavior at low shear rates and hydrodynamics becomes important at high shear rates.
Download or read book Colloids and the Depletion Interaction written by Henk N.W. Lekkerkerker and published by Springer Science & Business Media. This book was released on 2011-05-12 with total page 245 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloids are submicron particles that are ubiquitous in nature (milk, clay, blood) and industrial products (paints, drilling fluids, food). In recent decades it has become clear that adding depletants such as polymers or small colloids to colloidal dispersions allows one to tune the interactions between the colloids and in this way control the stability, structure and rheological properties of colloidal dispersions. This book offers a concise introduction to the fundamentals of depletion effects and their influence on the phase behavior of colloidal dispersions. Throughout the book, conceptual explanations are accompanied by experimental and computer simulation results. From the review by Kurt Binder: "They have succeeded in writing a monograph that is a very well balanced compromise between a very pedagogic introduction, suitable for students and other newcomers, and reviews of the advanced research trends in the field. Thus each chapter contains many and up to date references, but in the initial sections of the chapters, there are suggested exercises which will help the interested reader to recapitulate the main points of the treatment and to deepen his understanding of the subject. Only elementary knowledge of statistical thermodynamics is needed as a background for understanding the derivations presented in this book; thus this text is suitable also for advanced teaching purposes, useful of courses which deal with the physics for soft condensed matter. There does not yet exist any other book with a similar scope..... The readability of this book is furthermore enhanced by a list of symbols, and index of keywords, and last not least by a large number of figures, including many pedagogic sketches which were specifically prepared for this book. Thus, this book promises to be very useful for students and related applied sciences alike." Eur. Phys. J. E (2015) 38: 73
Download or read book Probing Out of Equilibrium Soft Matter written by Roberto Cerbino and published by Frontiers Media SA. This book was released on 2023-04-11 with total page 125 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Charged Colloidal Suspensions in Confined Geometries written by Ana Barreira Fontecha and published by . This book was released on 2009 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Colloidal Suspensions in Confined Geometries written by Clemens Bechinger and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Flow Properties of Colloidal Suspensions written by Bruce Andrew Firth and published by . This book was released on 1975 with total page 420 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Flow of Colloidal Suspensions Through Porous Media written by Robert John Hunter and published by . This book was released on 1962 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Flow induced Diffusion in Dilute Colloidal Suspensions written by Oleg Victor Bychuk and published by . This book was released on 1996 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Attractions on the Flow Properties of Dense Colloidal Suspensions written by Vijay Gopalakrishnan and published by . This book was released on 2004 with total page 216 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Phase Behavior and Effective Interactions in Colloidal Suspensions written by and published by Cuvillier Verlag. This book was released on 2007-04-25 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colloidal suspensions describe particles with size from typically a few nanometers to a few microns which are dispersed in a medium. In physics, in chemistry, and in biology colloids play an important role and the study of colloidal systems underwent a recent renaissance. This is based on the development of experimental techniques, the availability of extensive computer simulations and well-developed theoretical approaches. From a technological point of view, the relevance of micro- and nanostructured materials and the presence of colloids in nature and everyday life motivates study of this rich field. In this thesis the phase behavior and the effective interactions of colloidal suspensions in bulk, in contact with surfaces, and in confined geometry are studied. For mixtures of particles with hard-core interactions the model introduced by Asakura, Oosawa and Vrij provides an appropriate starting-point. Based on that model the free-volume theory and the density functional theory are employed. In experimental systems one faces particles with properties such as the size or the shape which are described by a distribution. To capture that issue a generalized approach based on free-volume theory for treating mixtures of colloids and a polydisperse depletion agent is presented. Within that approach it is possible to treat size and morphology polydispersity. A depletion agent with a bimodal distribution possessing two length scales can be studied. Though the Asakura-Oosawa-Vrij model describes a simple fluid - a mixture of hard spheres and ideal polymer - the phenomenology is rather rich: in contact with a wall one finds layering and wetting effects and in confined geometry of a narrow pore one finds capillary condensation. The competition between both effects manifests itself in thermodynamic properties like the excess colloid adsorption and the solvation force between the two confining walls. Solvent phase separation complicates the evaluation of interparticle interactions between the solute particles. We address this question for the wall-colloid and the colloid-colloid geometry. For a non-spherical particle the effect of curvature on thermodynamic quantities is studied.
Download or read book The Flow of Colloidal Suspensions Through Porous Media written by Robert Bruce Curry and published by . This book was released on 1960 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt:
