Role of polymer concentration and molecular weight on the rebounding behaviors of polymer solution droplet impacting on hydrophobic surfaces

2014 ◽  
Vol 18 (5-6) ◽  
pp. 1221-1232 ◽  
Author(s):  
Hyung Kyu Huh ◽  
Sungjune Jung ◽  
Kyung Won Seo ◽  
Sang Joon Lee
Keyword(s):  
Molecular Weight ◽  
Polymer Solution ◽  
Polymer Concentration ◽  
Hydrophobic Surfaces ◽  
Solution Droplet

scholarly journals Numerical Simulations of Polymer Solution Droplet Impact on Surfaces of Different Wettabilities

Processes ◽  
2019 ◽  
Vol 7 (11) ◽  
pp. 798 ◽  
Author(s):  
Tembely ◽  
Vadillo ◽  
Soucemarianadin ◽  
Dolatabadi
Keyword(s):  
Polymer Solution ◽  
Impact Analysis ◽  
Contact Angle Hysteresis ◽  
Polymer Concentration ◽  
Dynamic Contact ◽  
Droplet Impact ◽  
Droplet Spreading ◽  
Physically Based ◽  
Solution Droplet ◽  
Fluid Rheology

This paper presents a physically based numerical model to simulate droplet impact, spreading, and eventually rebound of a viscoelastic droplet. The simulations were based on the volume of fluid (VOF) method in conjunction with a dynamic contact model accounting for the hysteresis between droplet and substrate. The non‐Newtonian nature of the fluid was handled using FENE‐CR constitutive equations which model a polymeric fluid based on its rheological properties. A comparative simulation was carried out between a Newtonian solvent and a viscoelastic dilute polymer solution droplet. Droplet impact analysis was performed on hydrophilic and superhydrophobic substrates, both exhibiting contact angle hysteresis. The effect of substrates’ wettability on droplet impact dynamics was determined the evolution of the spreading diameter. While the kinematic phase of droplet spreading seemed to be independent of both the substrate and fluid rheology, the recoiling phase seemed highly influenced by those operating parameters. Furthermore, our results implied a critical polymer concentration in solution, between 0.25 and 2.5% of polystyrene (PS), above which droplet rebound from a superhydrophobic substrate could be curbed. The present model could be of particular interest for optimized 2D/3D printing of complex fluids.

Effect of the Initial Solute Concentration on the Flow Pattern Inside an Evaporating Polymer Solution Droplet on a Substrate

2007 ◽  
Author(s):  
Masayuki Kaneda ◽  
Kentarou Hyakuta ◽  
Hirotaka Ishizuka ◽  
Jun Fukai
Keyword(s):  
Contact Angle ◽  
Polymer Solution ◽  
Flow Pattern ◽  
Laser Sheet ◽  
Polymer Concentration ◽  
Internal Flow ◽  
Solute Concentration ◽  
Initial Solute ◽  
Solution Droplet ◽  
Source Flow

The internal flow of an evaporating polymer solution droplet on a substrate is experimentally studied. The flow visualization is carried out. The effect of the initial polymer concentration is further investigated. A polystyrene-acetophenone (PS-Ap) and a polystyrene-anisole (PS-Ani) solution are employed as the droplet. A nylon powder is mixed with the droplet for the visualization by a YAG-laser sheet light. The droplet evaporates after the settlement on the substrate. Without the polymer dissolved in the solvent, complicated flow is observed in both droplets. For the cases with dissolved polymer, the flow pattern is rectified. In the PS-Ap droplet, the source flow is observed for the initial solute mass fraction c0 = 0.005 – 0.20. This convection becomes strong as c0 increases. The mechanism of the flow inside the PS-Ap droplet can be understood by the combination of the natural convection and Marangoni convection due to the differences of the temperature and the solute concentration. As for the PS-Ani droplet, the evaporation process and the flow pattern are affected by c0. For the dilute solution (0 < c0 < 0.03), the contact angle decreases during the contact line receding. The observed flow pattern becomes similar to that in the PS-Ap droplet. At c0 = 0.08 – 0.2, the decline of the contact angle is remarkable and the direction of the internal flow becomes inverse. This flow mechanism cannot be clarified, but it may have the relations with the decreasing contact angle.

The Laboratory Evaluation of Several Polymer Solution Performances

2013 ◽  
Vol 734-737 ◽  
pp. 2549-2552
Author(s):  
Jiu Zhou Sun ◽  
Chang Bin Wang ◽  
Liang Kan ◽  
Ze Hua Wang
Keyword(s):  
Molecular Weight ◽  
Polymer Solution ◽  
Polymer Concentration ◽  
Laboratory Evaluation ◽  
Molecular Weight Polymer ◽  
Molecular Weights ◽  
Different Molecular Weight

The laboratory evaluation studied the matching relationship between different concentration polymer solution and the formation permeability,and also the matching relationship between different molecular weight polymer solution and the formation permeability. The influences on the solution viscoelasticity,which were caused by the polymer concentration and the molecular weights,were analysed by the laboratory evaluation tests on the viscoelasticity of the polymer solution.

scholarly journals The Thermoviscosifying Behavior of Water-Soluble Polymer Based on Graft Polymerization of Pluronic F127 with Acrylamide and 2-Acrylamido-2-methylpropane Sulfonic Acid Sodium Salt

Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1702 ◽  
Author(s):  
Quan ◽  
Xie ◽  
Su ◽  
Feng
Keyword(s):  
Molecular Weight ◽  
Polymer Solution ◽  
Sodium Salt ◽  
Polymer Concentration ◽  
Water Soluble ◽  
Pluronic F127 ◽  
Water Soluble Polymer ◽  
Practical Applications ◽  
Acid Sodium Salt ◽  
Methylpropionic Acid

A new concept of thermoviscosifying polymers is proposed to address the problems about decreasing viscosity of polymer solution under high temperatures. However, existing thermoviscosifying polymers have complicated synthesis processes and high costs, and both of them restrict the wide practical applications of thermoviscosifying polymers. Although polyethers have the characteristics of thermal gelatinization, they just display thermoviscosifying behaviors only under extremely high concentrations (>15 wt %). Therefore, the graft copolymerization of the commercialized Pluronic F127 (PEO100-PPO65-PEO100) with acrylamide and 2-acrylamide-methylpropionic acid sodium salt was studied here. A series of graft modified polyether polymers were prepared and it was expected to get thermoviscosifying polymers with high molecular weights and low association temperatures. Several factors on thermoviscosifying behaviors were investigated, such as polymerization condition, polymer concentration, hydrophilic monomer, molecular structure and molecular weight. It was also proven that the apparent viscosity of polymer solution is influenced by polymer concentration, molecular weight of polymer, and content of anion groups.

scholarly journals Adiponectin: Structure, Physiological Functions, Role in Diseases, and Effects of Nutrition

Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1180
Author(s):  
Kayvan Khoramipour ◽  
Karim Chamari ◽  
Amirhosein Ahmadi Hekmatikar ◽  
Amirhosein Ziyaiyan ◽  
Shima Taherkhani ◽  
...  
Keyword(s):  
Cardiovascular Disease ◽  
Amino Acids ◽  
Molecular Weight ◽  
Energy Regulation ◽  
Treatment Interventions ◽  
Adipose Tissues ◽  
Physiological Functions ◽  
Cellular Events ◽  
Healthy Nutrition

Adiponectin (a protein consisting of 244 amino acids and characterized by a molecular weight of 28 kDa) is a cytokine that is secreted from adipose tissues (adipokine). Available evidence suggests that adiponectin is involved in a variety of physiological functions, molecular and cellular events, including lipid metabolism, energy regulation, immune response and inflammation, and insulin sensitivity. It has a protective effect on neurons and neural stem cells. Adiponectin levels have been reported to be negatively correlated with cancer, cardiovascular disease, and diabetes, and shown to be affected (i.e., significantly increased) by proper healthy nutrition. The present review comprehensively overviews the role of adiponectin in a range of diseases, showing that it can be used as a biomarker for diagnosing these disorders as well as a target for monitoring the effectiveness of preventive and treatment interventions.

scholarly journals Study Rheological Behavior of Polymer Solution in Different-Medium-Injection-Tools

Polymers ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 319 ◽  
Author(s):  
Bin Huang ◽  
Xiaohui Li ◽  
Cheng Fu ◽  
Ying Wang ◽  
Haoran Cheng
Keyword(s):  
Molecular Weight ◽  
Polymer Solution ◽  
Oil Recovery ◽  
Injection Pressure ◽  
Injection Rate ◽  
Injection Velocity ◽  
Structural Parameter ◽  
Local Perturbation ◽  
Polymer Injection ◽  
Single Pipe

Previous studies showed the difficulty during polymer flooding and the low producing degree for the low permeability layer. To solve the problem, Daqing, the first oil company, puts forward the polymer-separate-layer-injection-technology which separates mass and pressure in a single pipe. This technology mainly increases the control range of injection pressure of fluid by using the annular de-pressure tool, and reasonably distributes the molecular weight of the polymer injected into the thin and poor layers through the shearing of the different-medium-injection-tools. This occurs, in order to take advantage of the shearing thinning property of polymer solution and avoid the energy loss caused by the turbulent flow of polymer solution due to excessive injection rate in different injection tools. Combining rheological property of polymer and local perturbation theory, a rheological model of polymer solution in different-medium-injection-tools is derived and the maximum injection velocity is determined. The ranges of polymer viscosity in different injection tools are mainly determined by the structures of the different injection tools. However, the value of polymer viscosity is mainly determined by the concentration of polymer solution. So, the relation between the molecular weight of polymer and the permeability of layers should be firstly determined, and then the structural parameter combination of the different-medium-injection-tool should be optimized. The results of the study are important for regulating polymer injection parameters in the oilfield which enhances the oil recovery with reduced the cost.

Neurofilament phosphorylation

1995 ◽  
Vol 73 (9-10) ◽  
pp. 575-592 ◽  
Author(s):  
Harish C. Pant ◽  
Veeranna
Keyword(s):  
Molecular Weight ◽  
Nervous System ◽  
Nervous Tissue ◽  
Important Determinant ◽  
Neurofilament Proteins ◽  
Neurofilament Phosphorylation ◽  
Axonal Compartment

Neurofilament proteins (NFPs) are highly phosphorylated molecules in the axonal compartment of the adult nervous system. The phosphorylation of NFP is considered an important determinant of filament caliber, plasticity, and stability. This process reflects the function of NFs during the lifetime of a neuron from differentiation in the embryo through long-term activity in the adult until aging and environmental insult leads to pathology and ultimately death. NF function is modulated by phosphorylation–dephosphorylation in each of these diverse neuronal states. In this review, we have summarized some of these properties of NFP in adult nervous tissue, mostly from work in our own laboratory. Identification of sites phosphorylated in vivo in high molecular weight NFP (NF-H) and properties of NF-associated and neural-specific kinases phosphorylating specific sites in NFP are described. A model to explain the role of NF phosphorylation in determining filament caliber, plasticity, and stability is proposed.Key words: neurofilament proteins, phosphorylation, kinases, phosphatases, regulators, inhibitors, multimesic complex, domains.

Detection of inducible nitric oxide synthase inSchistosoma japonicumandS. mansoni

2004 ◽  
Vol 78 (1) ◽  
pp. 47-50 ◽  
Author(s):  
X.-C. Long ◽  
M. Bahgat ◽  
K. Chlichlia ◽  
A. Ruppel ◽  
Y.-L. Li
Keyword(s):  
Nitric Oxide ◽  
Molecular Weight ◽  
Inducible Nitric Oxide Synthase ◽  
Mouse Liver ◽  
Apparent Molecular Weight ◽  
Western Blots ◽  
Oxide Synthase ◽  
Host Tissues ◽  
Inducible Nitric Oxide

AbstractSchistosoma japonicumandS. mansoniwere tested for reactivity with an anti-inducible nitric oxide (iNOS) antibody and the distribution of iNOS was studied by immunofluorescent tests in different stages of the parasites. Reactivity was associated with the tegument in both larval schistosomes (sporocysts and cercariae) and eggs. With adult worms, the majority of the immunofluorescence was predominantly subtegumental inS. japonicumand parenchymal inS. mansoni. Fluorescence was also observed in host tissues (snails and mouse liver). In Western blots, the enzyme ofS. japonicumhad an apparent molecular weight of about 210 kDa. The possible role of worm and host iNOS in the parasite–host interrelation remains to be clarified.

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