Highly non-additive symmetric mixtures at a wall.
1Department for the Modelling of Physico-Chemical Processes, Faculty of Chemistry, MCS University, 20031 Lublin, Poland. andrzej.patrykiejew@umcs.lublin.pl.
Physical Chemistry Chemical Physics : PCCP
|March 22, 2018
Summary
This study reveals complex wetting behaviors in non-additive mixtures, showing complete wetting below the demixing point and incomplete wetting above. Surface interactions significantly influence this fluid wetting phenomenon.
Area of Science:
- Physical Chemistry
- Surface Science
- Thermodynamics
Background:
- Understanding fluid behavior at interfaces is crucial in various chemical processes.
- Non-additive mixtures exhibit unique bulk properties, including closed immiscibility loops.
- Wetting phenomena describe how a liquid spreads over a solid surface.
Purpose of the Study:
- To investigate the wetting behavior of non-additive symmetric mixtures at non-selective walls.
- To analyze the influence of bulk immiscibility and surface-fluid interactions on wetting transitions.
- To characterize complex wetting scenarios near bulk demixing and tricritical points.
Main Methods:
- Grand Canonical Ensemble Monte Carlo (GCE-MC) simulations were employed.
- Simulations focused on mixtures with closed immiscibility loops in the bulk phase.
- Analysis of the adsorbed film composition and phase behavior at different temperatures and surface interactions.
Main Results:
- Complex wetting behavior was observed, including complete wetting below the bulk demixing point and incomplete wetting above.
- A second wetting transition was identified near the bulk tricritical point (λ-line).
- Complete wetting was also observed below, at, and above the bulk demixing temperature in systems with adsorbed film demixing.
Conclusions:
- The wetting behavior of these mixtures is highly sensitive to temperature and the strength of surface-fluid interactions.
- Non-additive mixtures with closed immiscibility loops display intricate wetting transitions.
- Simulation results provide insights into interfacial phenomena in complex fluid systems.
Related Concept Videos
03:27Mixtures of Acids
21.9K
The pH of a solution containing an acid can be determined using its acid dissociation constant and its initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending upon the relative strength of the acids and their dissociation constants.
A Mixture of a Strong Acid and a Weak Acid
In a mixture of a strong acid and a weak acid, the strong acid dissociates completely and becomes a source of almost all the hydronium ions...
A Mixture of a Strong Acid and a Weak Acid
In a mixture of a strong acid and a weak acid, the strong acid dissociates completely and becomes a source of almost all the hydronium ions...
21.9K
01:19Mixtures of Acids
1.1K
The pH of a solution containing an acid can be determined using its acid dissociation constant and initial concentration. If a solution contains two different acids, then its pH can be determined using one of several methods depending on the relative strength of the acids and their dissociation constants.
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...
In a strong and weak acid mixture, the strong acid dissociates completely and becomes a source of almost all the hydronium ions present in the solution. In contrast, the weak acid shows...
1.1K
01:07Symmetric Member in Bending
618
In the study of the mechanics of materials, analyzing the behavior of prismatic members under opposing couples is crucial for understanding internal stress distributions, which are essential for structural design. When subjected to couples, a prismatic member experiences internal forces that maintain equilibrium. A couple, characterized by two equal and opposite forces, creates a moment but no resultant force. The internal forces at any section cut of the member must balance these external...
618
01:27Conjugate Addition (1,4-Addition) vs Direct Addition (1,2-Addition)
4.4K
α,β-Unsaturated carbonyl compounds with two electrophilic sites, the carbonyl carbon, and the β carbon, are susceptible to nucleophilic attack via two modes: conjugate or 1,4-addition and direct or 1,2-addition.
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are...
Conjugate addition results in a thermodynamically stable product. The reaction retains the stronger C=O bond at the expense of the weaker C=C π bond. The process is slow as the β carbon is less electrophilic than the carbonyl carbon.
Direct addition products are...
4.4K
01:18Deformations in a Symmetric Member in Bending
528
When analyzing the deformation of a symmetric prismatic member subjected to bending by equal and opposite couples, it becomes clear that as the member bends, the originally straight lines on its wider faces curve into circular arcs, with a constant radius centered at a point known as Point C. This phenomenon helps to understand the stress and strain distribution within the member more clearly.
When the member is segmented into tiny cubic elements, it is observed that the primary stress...
When the member is segmented into tiny cubic elements, it is observed that the primary stress...
528
01:15Beams with Symmetric Loadings
432
The moment-area method is an analytical tool used in structural engineering to determine the slope and deflection of beams under various loads. Consider a cantilever with a concentrated load and moment at the free end. The first step is constructing a free-body diagram to calculate the reactions at the fixed end. Next, the bending moment diagram is plotted to visualize how the bending moment varies along the beam's length, focusing on points where the bending moment equals zero.
The M/EI...
The M/EI...
432