Solid–liquid transition of charge-stabilized colloidal dispersions: a single-component structure-function approach

We have extended the RavechéMountainStreett one-phasecriterion that governs the freezing of Lennard-Jones systems to a hard-core repulsive Yukawa-model (HCRYM) system. We find in the framework of the RogersYoung (RY) approximation for an OrnsteinZernike integral equation that an HCRYM fluid freezes when the ratio α = g(rmin)/g(rmax), where rmax is the distance corresponding to the maximum in the radial distribution function g(r) and rmin is the distance corresponding to the subsequent minimum in g(r), is approximately 0.215. To describe the freezing of charge-stabilized colloidal dispersions in electrolytes, which consist of colloidal macroions,electrolyte small ions, and solvent molecules, we employ the single-component model in which the colloidal particles interact through the effective screened Coulomb potential of Belloni. Whenthe macroion surface effective charge number is taken as an adjustable parameter, the theoretical freezing line predicted by the RY g(rmin)/g(rmax) = 0.215 RavechéMountainStreett one-phase criterion is in very good agreement with the corresponding experimental data.PACS Nos.: 61.25.Em, 61.20.Gy

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Solid-liquid transition induced by the anisotropic diffusion of colloidal particles

Chinese Physics B ◽

10.1088/1674-1056/ac1e19 ◽

2021 ◽

Author(s):

Fu-Jun Lin ◽

Jing-Jing Liao ◽

Jian-Chun Wu ◽

Bao-Quan Ai

Keyword(s):

Anisotropic Diffusion ◽

Colloidal Particles ◽

Liquid Transition ◽

Solid Liquid

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Tailoring the Morphology of Supraparticles by Primary Colloids with Different Shapes, Sizes and Dispersities

Crystals ◽

10.3390/cryst11020079 ◽

2021 ◽

Vol 11 (2) ◽

pp. 79

Author(s):

Wonmi Shim ◽

Chan Sik Moon ◽

Hyeonjin Kim ◽

Hyun Su Kim ◽

Haoxiang Zhang ◽

...

Keyword(s):

Composite Material ◽

Colloidal Particles ◽

Colloidal Dispersion ◽

Colloidal Dispersions ◽

Single Component ◽

Promising Method ◽

Shell Structures ◽

Core Shell ◽

Different Shapes ◽

Shape And Size

Surface-templated evaporation driven (STED) method is a promising method to fabricate supraparticles with various sizes, porosities, and shapes by drying colloidal dispersion drops on liquid repellent surfaces. Until now, for the method, only spherical shaped colloidal particles have been used as primary colloids. Here, we introduce six different shapes of nano-colloidal dispersions for the STED method: nanocubics, nanoplates, nanosheets, coffin-shaped nanoparticles (NPs), spherical NPs, and aggregates of NPs. It is confirmed that the shape and size of the primary colloids have little effect for drying the dispersion drop when a single component colloidal dispersion is dried. For heterogeneous supraparticles with composite material assembly, still the shape of the colloids has no influences, while the size and dispersity play roles for tuning the morphology of the supraparticles. From the results, we propose a way to fabricate homogeneous mixture, core/shell, and Janus core/shell structures of the supraparticles depending on the size and dispersity of the mixture colloidal dispersion. Indeed, knowledge on the effects of types of colloids would be of great importance for tailoring supraparticles.

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Reentrant Solid-Liquid Transition in Ionic Colloidal Dispersions by Varying Particle Charge Density

Physical Review Letters ◽

10.1103/physrevlett.80.5806 ◽

1998 ◽

Vol 80 (26) ◽

pp. 5806-5809 ◽

Cited By ~ 69

Author(s):

Junpei Yamanaka ◽

Hiroshi Yoshida ◽

Tadanori Koga ◽

Norio Ise ◽

Takeji Hashimoto

Keyword(s):

Charge Density ◽

Colloidal Dispersions ◽

Particle Charge ◽

Liquid Transition ◽

Solid Liquid

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Pressure variation of melting temperatures of alkali halides

International Journal of Modern Physics B ◽

10.1142/s021797921750031x ◽

2017 ◽

Vol 31 (05) ◽

pp. 1750031

Author(s):

Sayyadul Arafin ◽

Ram N. Singh

Keyword(s):

High Pressures ◽

A Priori ◽

Alkali Halides ◽

Industrial Applications ◽

Ambient Conditions ◽

Melting Temperatures ◽

Liquid Transition ◽

Wide Range ◽

Solid Liquid ◽

Good Agreement

The melting temperatures of alkali halides (LiCl, LiF, NaBr, NaCl, NaF, NaI, KBr, KCl, KF, KI, RbBr, RbCl, RbI and CsI) have been evaluated over a wide range of pressures. The solid–liquid transition of alkali halides is of considerable significance due to their huge industrial applications. Our formalism requires a priori knowledge of the bulk modulus and the Grüneisen parameter at ambient conditions to compute [Formula: see text] at high pressures. The computed values are in very good agreement with the available experimental results. The formalism can satisfactorily be used to compute [Formula: see text] at high pressures where the experimental data are scanty. Most of the melting curves ([Formula: see text] versus [Formula: see text]) exhibit nonlinear variation with increasing pressure having curvatures downward and exhibit a maximum in some cases like NaCl, RbBr, RbCl and RbI. The values of [Formula: see text] and [Formula: see text] corresponding to the maxima of the curves are given.

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Fast Overlap Detection between Hard-Core Colloidal Cuboids and Spheres. The OCSI Algorithm

Algorithms ◽

10.3390/a14030072 ◽

2021 ◽

Vol 14 (3) ◽

pp. 72

Author(s):

Luca Tonti ◽

Alessandro Patti

Keyword(s):

Colloidal Particles ◽

Dynamic Properties ◽

Wide Spectrum ◽

Three Dimensional ◽

Hard Core ◽

Detection Algorithm ◽

Three Dimensional Objects ◽

Aggregation Behaviour ◽

Sphere Radius ◽

User Friendly

Collision between rigid three-dimensional objects is a very common modelling problem in a wide spectrum of scientific disciplines, including Computer Science and Physics. It spans from realistic animation of polyhedral shapes for computer vision to the description of thermodynamic and dynamic properties in simple and complex fluids. For instance, colloidal particles of especially exotic shapes are commonly modelled as hard-core objects, whose collision test is key to correctly determine their phase and aggregation behaviour. In this work, we propose the Oriented Cuboid Sphere Intersection (OCSI) algorithm to detect collisions between prolate or oblate cuboids and spheres. We investigate OCSI’s performance by bench-marking it against a number of algorithms commonly employed in computer graphics and colloidal science: Quick Rejection First (QRI), Quick Rejection Intertwined (QRF) and a vectorized version of the OBB-sphere collision detection algorithm that explicitly uses SIMD Streaming Extension (SSE) intrinsics, here referred to as SSE-intr. We observed that QRI and QRF significantly depend on the specific cuboid anisotropy and sphere radius, while SSE-intr and OCSI maintain their speed independently of the objects’ geometry. While OCSI and SSE-intr, both based on SIMD parallelization, show excellent and very similar performance, the former provides a more accessible coding and user-friendly implementation as it exploits OpenMP directives for automatic vectorization.

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