scholarly journals Surface morphology of electrospun PLA fibers: mechanisms of pore formation

RSC Advances ◽  
2014 ◽  
Vol 4 (83) ◽  
pp. 44082-44088 ◽  
Author(s):  
Lakshmi Natarajan ◽  
Jackie New ◽  
Aravind Dasari ◽  
Suzhu Yu ◽  
Munirah Abdul Manan
Keyword(s):  
Phase Separation ◽  
Relative Humidity ◽  
Surface Morphology ◽  
Pore Formation ◽  
Surface Pores

Interaction of relative humidity with solvent(s) is relatively more important in obtaining surface pores than solvent volatility and phase separation.

scholarly journals Phase separation during blood spreading

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Houssine Benabdelhalim ◽  
David Brutin
Keyword(s):  
Phase Separation ◽  
Relative Humidity ◽  
Whole Blood ◽  
Crime Scene ◽  
Blood Pool ◽  
Ambient Temperatures ◽  
Surrounding Environment ◽  
Crime Scene Investigators ◽  
Almost All ◽  
Pool Area

AbstractBlood pools can spread on several types of substrates depending on the surrounding environment and conditions. Understanding the influence of these parameters on the spreading of blood pools can provide crime scene investigators with useful information. The focus of the present study is on phase separation, that is, when the serum spreads outside the main blood pool. For this purpose, blood pools with constant initial masses on wooden floors that were either varnished or not were created at ambient temperatures of $$21~^{\circ }\hbox {C}$$ 21 ∘ C , $$29~^{\circ }\hbox {C}$$ 29 ∘ C , and $$37~^{\circ }\hbox {C}$$ 37 ∘ C with a relative humidity varying from 20 to 90%. The range $$21~^{\circ }\hbox {C}$$ 21 ∘ C to $$37~^{\circ }\hbox {C}$$ 37 ∘ C covers almost all worldwide indoor cases. The same whole blood from the same donor was used for all experiments. As a result, an increase in relative humidity was found to result in an increase in the final pool area. In addition, at the three different experimental temperatures, the serum spread outside the main pool at relative humidity levels above 50%. This phase separation is more significant on varnished substrates, and does not lead to any changes in the drying morphology. This phenomenon is explained by the competition between coagulation and evaporation.

scholarly journals Liquid–liquid phase separation in particles containing organics mixed with ammonium sulfate, ammonium bisulfate, ammonium nitrate or sodium chloride

2013 ◽  
Vol 13 (23) ◽  
pp. 11723-11734 ◽  
Author(s):  
Y. You ◽  
L. Renbaum-Wolff ◽  
A. K. Bertram
Keyword(s):  
Phase Separation ◽  
Sodium Chloride ◽  
Liquid Phase ◽  
Relative Humidity ◽  
Ammonium Sulfate ◽  
Inorganic Salt ◽  
Liquid Phase Separation ◽  
Inorganic Salts ◽  
Organic Species ◽  
Liquid Liquid Phase Separation

Abstract. As the relative humidity varies from high to low values in the atmosphere, particles containing organic species and inorganic salts may undergo liquid–liquid phase separation. The majority of the laboratory work on this subject has used ammonium sulfate as the inorganic salt. In the following we studied liquid–liquid phase separation in particles containing organics mixed with the following salts: ammonium sulfate, ammonium bisulfate, ammonium nitrate and sodium chloride. In each experiment one organic was mixed with one inorganic salt and the liquid–liquid phase separation relative humidity (SRH) was determined. Since we studied 23 different organics mixed with four different salts, a total of 92 different particle types were investigated. Out of the 92 types, 49 underwent liquid–liquid phase separation. For all the inorganic salts, liquid–liquid phase separation was never observed when the oxygen-to-carbon elemental ratio (O : C) &amp;geq; 0.8 and was always observed for O : C < 0.5. For 0.5 &amp;leq; O : C < 0.8, the results depended on the salt type. Out of the 23 organic species investigated, the SRH of 20 organics followed the trend: (NH4)2SO4 &amp;geq; NH4HSO4 &amp;geq; NaCl &amp;geq; NH4NO3. This trend is consistent with previous salting out studies and the Hofmeister series. Based on the range of O : C values found in the atmosphere and the current results, liquid–liquid phase separation is likely a frequent occurrence in both marine and non-marine environments.

scholarly journals Do ZnO and Al2O3 Nanoparticles Improve the Anti-Bacterial Properties of Cellulose Acetate-Chitosan Membrane?

2018 ◽  
Vol 156 ◽  
pp. 08009 ◽  
Author(s):  
Titik Istirokhatun ◽  
Ulva Yuni ◽  
Pertiwi Andarani ◽  
Heru Susanto
Keyword(s):  
Antimicrobial Activity ◽  
Phase Separation ◽  
Surface Morphology ◽  
Cellulose Acetate ◽  
Water Permeability ◽  
Al2o3 Nanoparticles ◽  
Gram Negative Bacteria ◽  
Gram Negative ◽  
Chitosan Membrane ◽  
Chitosan Membranes

Biofouling, due to the existence of bacteria in water, becomes one of the barriers in cellulose acetate (CA) membrane applications. Although chitosan has been incorporated into CA membranes, its antimicrobial activity has not been improved significantly yet. In this study, cellulose acetate-chitosan membranes were prepared by modification using ZnO and Al2O3 nanoparticles during phase separation method. The membranes were then characterized in term of water permeability, and surface morphology. The anti-bacteria property was examined by using gram-negative bacteria. Modification of cellulose acetate-chitosan membranes with ZnO and Al2O3 nanoparticles have not shown optimal results where no clear zones around the membrane are visible.

scholarly journals Coupling between pore formation and phase separation in charged lipid membranes

2015 ◽  
Vol 92 (6) ◽  
Author(s):  
Hiroki Himeno ◽  
Hiroaki Ito ◽  
Yuji Higuchi ◽  
Tsutomu Hamada ◽  
Naofumi Shimokawa ◽  
...  
Keyword(s):  
Phase Separation ◽  
Lipid Membranes ◽  
Pore Formation

scholarly journals Effect of TiO2 Powder on the Surface Morphology of Micro/Nanoporous Structured Hydrophobic Fluoropolymer Based Composite Material

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Bichitra Nanda Sahoo ◽  
Balasubramanian Kandasubramanian ◽  
Amrutha Thomas
Keyword(s):  
Phase Separation ◽  
Surface Morphology ◽  
Polymer Composite ◽  
Polyvinylidene Fluoride ◽  
Industrial Applications ◽  
Nanoporous Structure ◽  
Hydrophobic Surfaces ◽  
Water Contact ◽  
Maximum Water ◽  
The Impact

The present work reports a simple and effective way to produce hydrophobic foams with polyvinylidene fluoride (PVDF) and TiO2 by using a phase separation technique. This method involved the phase separation during the deposition of PVDF from its DMF solution with nonsolvent water in the presence of TiO2. The surface morphology of hydrophobic surfaces was characterized by Field Emission Scanning Electron Microscope (FESEM). The maximum water contact angle of 129° was observed. The results confirm that the surface texture of polymer composite exhibits mixture of microporous and nanoporous structure. The impact of TiO2 on the wettability property of polymer composite has been studied. The proposed methodology might find applications in the preparation of hydrophobic surfaces for industrial applications.

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