Kinetics of liquid–liquid phase separation in a binary mixture with miscibility gap: Study of noncritical mixtures of 2,6‐dimethyl pyridine/water near the lower critical point

1990 ◽  
Vol 93 (6) ◽  
pp. 4349-4356 ◽  
Author(s):  
W. Mayer ◽  
D. Woermann
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Binary Mixture ◽  
Critical Point ◽  
Liquid Phase Separation ◽  
Miscibility Gap ◽  
Kinetics Of ◽  
Liquid Liquid Phase Separation

scholarly journals Computation of liquid-liquid equilibria and phase stabilities: implications for RH-dependent gas/particle partitioning of organic-inorganic aerosols

2010 ◽  
Vol 10 (16) ◽  
pp. 7795-7820 ◽  
Author(s):  
A. Zuend ◽  
C. Marcolli ◽  
T. Peter ◽  
J. H. Seinfeld
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Water Solubility ◽  
Inorganic Compounds ◽  
Liquid Phase Separation ◽  
Miscibility Gap ◽  
Inorganic Aerosols ◽  
Particulate Mass ◽  
Inorganic Aerosol ◽  
Liquid Liquid Phase Separation

Abstract. Semivolatile organic and inorganic aerosol species partition between the gas and aerosol particle phases to maintain thermodynamic equilibrium. Liquid-liquid phase separation into an organic-rich and an aqueous electrolyte phase can occur in the aerosol as a result of the salting-out effect. Such liquid-liquid equilibria (LLE) affect the gas/particle partitioning of the different semivolatile compounds and might significantly alter both particle mass and composition as compared to a one-phase particle. We present a new liquid-liquid equilibrium and gas/particle partitioning model, using as a basis the group-contribution model AIOMFAC (Zuend et al., 2008). This model allows the reliable computation of the liquid-liquid coexistence curve (binodal), corresponding tie-lines, the limit of stability/metastability (spinodal), and further thermodynamic properties of multicomponent systems. Calculations for ternary and multicomponent alcohol/polyol-water-salt mixtures suggest that LLE are a prevalent feature of organic-inorganic aerosol systems. A six-component polyol-water-ammonium sulphate system is used to simulate effects of relative humidity (RH) and the presence of liquid-liquid phase separation on the gas/particle partitioning. RH, salt concentration, and hydrophilicity (water-solubility) are identified as key features in defining the region of a miscibility gap and govern the extent to which compound partitioning is affected by changes in RH. The model predicts that liquid-liquid phase separation can lead to either an increase or decrease in total particulate mass, depending on the overall composition of a system and the particle water content, which is related to the hydrophilicity of the different organic and inorganic compounds. Neglecting non-ideality and liquid-liquid phase separations by assuming an ideal mixture leads to an overestimation of the total particulate mass by up to 30% for the composition and RH range considered in the six-component system simulation. For simplified partitioning parametrizations, we suggest a modified definition of the effective saturation concentration, Cj*, by including water and other inorganics in the absorbing phase. Such a Cj* definition reduces the RH-dependency of the gas/particle partitioning of semivolatile organics in organic-inorganic aerosols by an order of magnitude as compared to the currently accepted definition, which considers the organic species only.

Microstructure Formation and Nanoindentation Behavior of Rapidly Solidified Cu-Fe-Zr Immiscible Alloys

2020 ◽  
Vol 993 ◽  
pp. 39-44
Author(s):  
Xiao Jun Sun ◽  
Jie He ◽  
Jiu Zhou Zhao
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Secondary Phase ◽  
Atomic Ratio ◽  
Liquid Phase Separation ◽  
Miscibility Gap ◽  
Rapidly Solidified ◽  
Liquid Liquid Phase Separation ◽  
Zr Alloy ◽  
Liquid Miscibility Gap

The binary Cu-Fe system is characterized by a metastable liquid miscibility gap. WhenZr is added into the Cu-Fe alloy, the miscibility gap can be extended into Cu-Fe-Zr ternary system. In the present study Cu-Fe-Zr alloys were prepared by single-roller melting-spinning method, and the samples were characterized by the SEM, EDS, HRTEM and nanoidentation. The results show that liquid-liquid phase separation into CuZr-rich and FeZr-rich liquids takes place during rapid cooling the Cu-Fe-Zr alloy, and the mechanism depends on the atomic ratio of Cu to Fe. With increasing Zr content, the size of secondary phase formed by the liquid-liquid phase separation reduces to nanoscale. The structure with amorphous Cu-rich nanoparticles embedded in the amorphous Fe-rich matrix was obtained in the as-quenched Cu20Fe20Zr60 alloy. For its structure particularity of the Cu20Fe20Zr60 sample, mechanical evaluation was carried out by using nanoindentation.

scholarly journals Liquid-liquid phase separation and fibrillization of tau are independent processes with overlapping conditions

2019 ◽  
Author(s):  
Yanxian Lin ◽  
Yann Fichou ◽  
Zhikai Zeng ◽  
Nicole Y. Hu ◽  
Songi Han
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Liquid Phase Separation ◽  
Amyloid Aggregation ◽  
Physiological Conditions ◽  
Three Stages ◽  
Tau Aggregation ◽  
Kinetics Of ◽  
Liquid Liquid Phase Separation

AbstractAmyloid aggregation of the microtubule binding protein tau is a hallmark of Alzheimer’s disease and many other neurodegenerative diseases. Recently, tau has been found to undergo liquid-liquid phase separation (LLPS) near physiological conditions. Although LLPS and aggregation have been shown to simultaneously occur under certain common conditions, it remains to be seen whether tau LLPS promotes aggregation, or if they are two independent processes. In this study, we address this question by combining multiple biochemical and biophysical assays in vitro. We investigated the impacts of LLPS on tau aggregation at three stages: conformation of tau, kinetics of aggregation and fibril quantity. We showed that none of these properties are influenced directly by LLPS, while amyloid aggregation propensity of tau can be altered without affecting its LLPS behavior. LLPS and amyloid aggregation of tau occur under overlapping conditions of enhanced intermolecular interactions and localization, but are two independent processes.

Sign in / Sign up

Export Citation Format

Share Document