Formation of macroporous poly(acrylamide) hydrogels in DMSO/water mixture: Transition from cryogelation to phase separation copolymerization

2008 ◽  
Vol 68 (10) ◽  
pp. 1467-1475 ◽  
Author(s):  
M. Murat Ozmen ◽  
Oguz Okay
Keyword(s):  
Phase Separation ◽  
Water Mixture ◽  
Poly Acrylamide

scholarly journals Experimental investigation of multiphase separation in different flow regimes through T-junction with an expander section

2019 ◽  
Vol 13 (2) ◽  
pp. 5163-5181
Author(s):  
Z. Q. Memon ◽  
W. Pao ◽  
F. Hashim ◽  
S. Ahmed
Keyword(s):  
Experimental Data ◽  
Phase Separation ◽  
Slug Flow ◽  
Vertical Plane ◽  
Flow Regimes ◽  
Diameter Ratio ◽  
Superficial Velocity ◽  
Inlet Section ◽  
Water Mixture ◽  
Gas Velocity

The experimental data for phase separation of the air-water mixture in a T-Junction with the expander section after the branch arm is presented in this work. The main and run arms of the T-junction are directed along the horizontal plane with the branch arm positioned in the vertical plane. The diameter of the main arm is 74 mm, with diameter ratio(s) of, 0.67, and 0.33 in relation to branch arm. At the inlet section of the T-junction, the flow regimes generated were stratified, stratified wavy and slug flow. At the inlet, the air and water superficial velocities are in the range of 0.25 - 0.140 m/s and 0.14-0.78 m/s respectively. The effect of the expander section after the branch arm, the air superficial velocity USA and water superficial velocity USw on liquid carryover (WL3/WL1)max in branch arm have been studied. Based on the experimental data obtained for T-junction with expander section, complete phase separation of air and water was observed in stratified and stratified wavy flow for all superficial velocities and improved phase separation for slug flow. In slug flow, increasing the liquid superficial velocity improves the phase separation but increasing the gas velocity decreases the phase separation. Finally, the volume weighted phase in this new T-junction design is compared with the phase separation data of a simple T-junction.

scholarly journals Matrix-Induced Sugaring-Out: A Simple and Rapid Sample Preparation Method for the Determination of Neonicotinoid Pesticides in Honey

Molecules ◽  
2019 ◽  
Vol 24 (15) ◽  
pp. 2761 ◽  
Author(s):  
Wenbin Chen ◽  
Siyuan Wu ◽  
Jianing Zhang ◽  
Fengjie Yu ◽  
Jianbo Hou ◽  
...  
Keyword(s):  
Phase Separation ◽  
Sample Preparation ◽  
Preparation Method ◽  
Liquid Extraction ◽  
Subzero Temperature ◽  
Water Mixture ◽  
Sample Preparation Method ◽  
Liquid Liquid Extraction ◽  
Neonicotinoid Pesticides

In the present work, we developed a simple and rapid sample preparation method for the determination of neonicotinoid pesticides in honey based on the matrix-induced sugaring-out. Since there is a high concentration of sugars in the honey matrix, the honey samples were mixed directly with acetonitrile (ACN)-water mixture to trigger the phase separation. Analytes were extracted into the upper ACN phase without additional phase separation agents and injected into the HPLC system for the analysis. Parameters of this matrix-induced sugaring-out method were systematically investigated. The optimal protocol involves 2 g honey mixed with 4 mL ACN-water mixture (v/v, 60:40). In addition, this simple sample preparation method was compared with two other ACN-water-based homogenous liquid-liquid extraction methods, including salting-out assisted liquid-liquid extraction and subzero-temperature assisted liquid-liquid extraction. The present method was fully validated, the obtained limits of detection (LODs) and limits of quantification (LOQs) were from 21 to 27 and 70 to 90 μg/kg, respectively. Average recoveries at three spiked levels were in the range of 91.49% to 97.73%. Precision expressed as relative standard deviations (RSDs) in the inter-day and intra-day analysis were all lower than 5%. Finally, the developed method was applied for the analysis of eight honey samples, results showed that none of the target neonicotinoid residues were detected.

Phase separation during the formation of poly(acrylamide) hydrogels

Polymer ◽  
2000 ◽  
Vol 41 (15) ◽  
pp. 5729-5735 ◽  
Author(s):  
S Durmaz ◽  
O Okay
Keyword(s):  
Phase Separation ◽  
Poly Acrylamide

scholarly journals Surface-Engineered Inorganic Nanoporous Membranes for Vapor and Pervaporative Separations of Water–Ethanol Mixtures

Membranes ◽  
2018 ◽  
Vol 8 (4) ◽  
pp. 95 ◽  
Author(s):  
Michael Hu ◽  
Chaiwat Engtrakul ◽  
Brian Bischoff ◽  
Mi Lu ◽  
Mussie Alemseghed
Keyword(s):  
Phase Separation ◽  
Vapor Phase ◽  
Porous Ceramic ◽  
Temperature Tolerance ◽  
Size Exclusion ◽  
Nanoporous Membranes ◽  
Water Mixture ◽  
Inorganic Membranes ◽  
Phase Separations ◽  
Separation Selectivity

Surface wettability-tailored porous ceramic/metallic membranes (in the tubular and planar disc form) were prepared and studied for both vapor-phase separation and liquid pervaporative separations of water-ethanol mixtures. Superhydrophobic nanoceramic membranes demonstrated more selective permeation of ethanol (relative to water) by cross-flow pervaporation of liquid ethanol–water mixture (10 wt % ethanol feed at 80 °C). In addition, both superhydrophilic and superhydrophobic membranes were tested for the vapor-phase separations of water–ethanol mixtures. Porous inorganic membranes having relatively large nanopores (up to 8-nm) demonstrated good separation selectivity with higher permeation flux through a non-molecular-sieving mechanism. Due to surface-enhanced separation selectivity, larger nanopore-sized membranes (~5–100 nm) can be employed for both pervaporation and vapor phase separations to obtain higher selectivity (e.g., permselectivity for ethanol of 13.9 during pervaporation and a vapor phase separation factor of 1.6), with higher flux due to larger nanopores than the traditional size-exclusion membranes (e.g., inorganic zeolite-based membranes having sub-nanometer pores). The prepared superhydrophobic porous inorganic membranes in this work showed good thermal stability (i.e., the large contact angle remains the same after 300 °C for 4 h) and chemical stability to ethanol, while the silica-textured superhydrophilic surfaced membranes can tolerate even higher temperatures. These surface-engineered metallic/ceramic nanoporous membranes should have better high-temperature tolerance for hot vapor processing than those reported for polymeric membranes.

Cluster Formation of 1-Butanol–Water Mixture Leading to Phase Separation

2004 ◽  
Vol 33 (6/7) ◽  
pp. 721-732 ◽  
Author(s):  
Akihiro Wakisaka ◽  
Shunsuke Mochizuki ◽  
Hitomi Kobara
Keyword(s):  
Phase Separation ◽  
Cluster Formation ◽  
Water Mixture

Hidden Minima of the Gibbs Free Energy Revealed in a Phase Separation in Polymer/Surfactant/Water Mixture

2005 ◽  
Vol 109 (18) ◽  
pp. 8533-8537 ◽  
Author(s):  
R. Hołyst ◽  
K. Staniszewski ◽  
A. Patkowski ◽  
J. Gapiński
Keyword(s):  
Free Energy ◽  
Phase Separation ◽  
Gibbs Free Energy ◽  
Water Mixture ◽  
Polymer Surfactant

scholarly journals The Crystallization of Active Pharmaceutical Ingredients with Low Melting Points in the Presence of Liquid–Liquid Phase Separation

Crystals ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 1326
Author(s):  
Wei Han Lin ◽  
Zai-Qun Yu ◽  
Pui Shan Chow ◽  
Reginald Beng Hee Tan
Keyword(s):  
Phase Separation ◽  
Liquid Phase ◽  
Hydroxypropyl Methylcellulose ◽  
Tween 80 ◽  
Liquid Phase Separation ◽  
Water Mixture ◽  
Active Pharmaceutical Ingredients ◽  
Melting Points ◽  
Pharmaceutical Ingredients ◽  
Liquid Liquid Phase Separation

Liquid–liquid phase separation (LLPS) during the crystallization of active pharmaceutical ingredients (APIs) often causes agglomeration and other quality issues in crystal products; thus, it should be avoided if possible. However, LLPS in the crystallization of APIs with low melting points cannot be circumvented in some cases due to yield considerations. The crystallization of ibuprofen in an ethanol/water mixture was studied to explore methods to reduce agglomeration in the presence of LLPS. It was found that unseeded crystallization produced agglomerates when LLPS took place. The two liquid phases resulting from LLPS underwent LLPS again when they were cooled separately, indicating the dynamic nature of LLPS. Seeding and seed ageing at a low supersaturation were very effective in mitigating agglomeration. The effects of two widely used surfactants, i.e., Tween 80 and hydroxypropyl methylcellulose (HPMC), on LLPS and crystallization were confirmed preliminarily. More work needs to be conducted to explore their usefulness in LLPS handling. The findings and techniques presented in this study may be applicable to the crystallization of other APIs with low melting points.

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