Difference between revisions of "Surface tension"

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(Topological Changes in Bipolar Nematic Droplets under Flow)
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Fernández-Nieves et. al. describe how they can change the configuration of the defects and director field in nematic liquid crystal droplets immersed in water. They use microfluidics to periodically change from bipolar and escaped concentric configurations, and when flow is stopped the droplets remain in whichever configuration they are in, even tough the bipolar state has a lower energy. The surface tension between the liquid crystal and the water stabilizes the droplets and determines their shape.
 
Fernández-Nieves et. al. describe how they can change the configuration of the defects and director field in nematic liquid crystal droplets immersed in water. They use microfluidics to periodically change from bipolar and escaped concentric configurations, and when flow is stopped the droplets remain in whichever configuration they are in, even tough the bipolar state has a lower energy. The surface tension between the liquid crystal and the water stabilizes the droplets and determines their shape.
  
===[[Self-assembled Shells Composed of Colloidal Particles: Fabrication and Characterization]]
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===[[Self-assembled Shells Composed of Colloidal Particles: Fabrication and Characterization]]===
 
Hsu et. al. showed how they can influence the morphology and mechanical properties of self-assembled polystyrene colloidal monolayers around emulsified drops by tuning the surface tension, molecular interaction, and stabilization of organic/water emulsions. Various emulsions were made using different solvents and stabilization techniques to explore how self-assembly was effected by solution and post-assembly parameters. The morphology and mechanical properties of each different emulsion were documented using scanning electron microscopy and axisymmetric compression. Surface tension governed both the assembly structure and the feasibility of the colloidal monolayers to act as size sieves for controlled liquid release.
 
Hsu et. al. showed how they can influence the morphology and mechanical properties of self-assembled polystyrene colloidal monolayers around emulsified drops by tuning the surface tension, molecular interaction, and stabilization of organic/water emulsions. Various emulsions were made using different solvents and stabilization techniques to explore how self-assembly was effected by solution and post-assembly parameters. The morphology and mechanical properties of each different emulsion were documented using scanning electron microscopy and axisymmetric compression. Surface tension governed both the assembly structure and the feasibility of the colloidal monolayers to act as size sieves for controlled liquid release.
  

Revision as of 21:44, 14 October 2012

Definition

Surface tension is a property of liquid surfaces caused by cohesion. Cohesion is the physical property resulting from the intermolecular forces attracting like-molecules. The molecules on the surface of a liquid have a greater attraction to like-molecules around them than to unlike-molecules.

Molecules on the surface of a liquid experience an inward force balanced by the resistance to compression. Another important point in understanding surface tension is the liquid molecules seek the lowest possible surface area. This is the reason that liquids form droplets on hydrophobic surfaces. The interface of lke-molecules has a lower energy than the interface of unlike-molecules, therefore surface molecules seek to have as many like-molecule interfaces as possible resulting in the lowest surface area.

Units

Surface tension (<math>\gamma</math>) has dimensions of force per unit length, <math>\frac{F} {L}</math>.

Examples

Topological Changes in Bipolar Nematic Droplets under Flow

Fernández-Nieves et. al. describe how they can change the configuration of the defects and director field in nematic liquid crystal droplets immersed in water. They use microfluidics to periodically change from bipolar and escaped concentric configurations, and when flow is stopped the droplets remain in whichever configuration they are in, even tough the bipolar state has a lower energy. The surface tension between the liquid crystal and the water stabilizes the droplets and determines their shape.

Self-assembled Shells Composed of Colloidal Particles: Fabrication and Characterization

Hsu et. al. showed how they can influence the morphology and mechanical properties of self-assembled polystyrene colloidal monolayers around emulsified drops by tuning the surface tension, molecular interaction, and stabilization of organic/water emulsions. Various emulsions were made using different solvents and stabilization techniques to explore how self-assembly was effected by solution and post-assembly parameters. The morphology and mechanical properties of each different emulsion were documented using scanning electron microscopy and axisymmetric compression. Surface tension governed both the assembly structure and the feasibility of the colloidal monolayers to act as size sieves for controlled liquid release.

References

http://en.wikipedia.org/wiki/Cohesion_%28chemistry%29

http://en.wikipedia.org/wiki/Surface_tension

Keyword in references:

Capillary rise between elastic sheets

Contact angle associated with thin liquid films in emulsions

Controlled Assembly of Jammed Colloidal Shells on Fluid Droplets

Controlling the Fiber Diameter during electrospinning

Krafft Points, Critical Micelle Concentrations, Surface Tension, and Solubilizing Power of Aqueous Solutions of Fluorinated Surfactants

Surface-Tension-Induced Synthesis of Complex Particles Using Confined Polymeric Fluids

The Deformation of an Elastic Substrate by a Three-Phase Contact Line E. R. Jerison

Thermodynamic deviations of the mechanical equilibrium conditions for fluid surfaces: Young's and Laplace's equations

Substrate Curvature Resulting from the Capillary Forces of a Liquid Drop

Steering nanofibers: An integrative approach to bio-inspired fiber fabrication and assembly

Liquid-infused structured surfaces with exceptional anti-biofouling performance

Liquid-Infused Nanostructured Surfaces with Extreme Anti-Ice and Anti-Frost Performance

How aphids lose their marbles

The viscous catenary

Elasticity of an interfacial particle raft

The wall-induced motion of a floating flexible train

Onset of Buckling in Drying Droplets of Colloidal Suspensions

Hydrodynamical models for the chaotic dripping faucet

The ‘‘Cheerios effect’’

Non-spherical bubbles

Wetting in Color: Colorimetric Differentiation of Organic Liquids with High Selectivity

Bifurcation of liquid drops

Acoustic Energy Storage in Single Bubble Sonoluminescence

Why air bubbles in water glow so easily

Analysis of Rayleigh–Plesset dynamics for sonoluminescing bubbles

Electrospinning: A whipping fluid jet generates submicron polymer fibers

Collapsing bacterial cylinders

Elastic Instability in Growing Yeast Colonies

Electric-field-induced capillary attraction between like-charged particles at liquid interfaces

Dynamics of foam drainage

Breakdown of scaling in droplet fission at high Reynolds number

Phase diagrams for sonoluminescing bubbles

On the bursting of viscous films

Linear stability and transient growth in driven contact lines

Mechanisms for Stable Single Bubble Sonoluminescence

Pinching threads, singularities and the number 0.0304 . . .

Single-bubble sonoluminescence

Thermal bending of liquid sheets and jets

Self-Assembly of Spherical Particles on an Evaporating Sessile Droplet

Electrospinning and electrically forced jets. I. Stability theory

Nanometer Patterning with Ice

Capillary rise between elastic sheets

Gravitational Stability of Suspensions of Attractive Colloidal Particles

A Quantitative Analysis of Contractility in Active Cytoskeletal Protein Networks

Equilibrium of an elastically confined liquid drop

Hygromorphs: from pine cones to biomimetic bilayers

Flip-Flop-Induced Relaxation of Bending Energy: Implications for Membrane Remodeling

Control of Shape and Size of Nanopillar Assembly by Adhesion-Mediated Elastocapillary Interaction

How wet paper curls

Buckling of a thin-layer Couette flow

Shock-driven jamming and periodic fracture of particulate rafts

A simple model for nanofiber formation by rotary jet-spinning

Hydrodynamics of Writing with Ink

Soft catenaries

Minimal surfaces bounded by elastic lines

Scale and Nature of Sulcification Patterns

Mitosis: Taking the Measure of Spindle Length

Fluctuations in membranes with crystalline and hexatic order

Evolving crack patterns in thin films with the extended finite element method

Reliability of Interconnect Structures

New directions in mechanics

Templated Self-Assembly Over Patterned Electrodes by an Applied Electric Field: Geometric Constraints and Diversity of Materials

Snap-through Expansion of a Gas Bubble in an Elastomer

Creasing instability of elastomer films

Analytical Solutions of Polymeric Gel Structures under Buckling and Wrinkle

Concurrent electromigration and creep in lead-free solder

Measuring the elastic modulus of microgels using microdrops

Phase switching of ordered arrays of liquid crystal emulsions

High-throughput injection with microfluidics using picoinjectors

One-step formation of multiple emulsions in microfluidics

Air-bubble-triggered drop formation in microfluidics

A new device for the generation of microbubbles

Surface-Tension-Induced Synthesis of Complex Particles Using Confined Polymeric Fluids

Diffusing-wave-spectroscopy measurements of viscoelasticity of complex fluids

Emulsion glasses: A dynamic light-scattering study

Osmotic pressure and viscoelastic shear moduli of concentrated emulsions

Optical Measurements of Frequency-Dependent Linear Viscoelastic Moduli of Complex Fluids

Drying of Complex Suspensions

Efficient encapsulation with plug-triggered drop formation

Measuring the elastic modulus of microgels using microdrops

Valve-based flow focusing for drop formation

Impact of inlet channel geometry on microfluidic drop formation

Microfluidic sorting with high-speed single-layer membrane valves

Electrocoalescence of drops synchronized by size-dependent flow in microfluidic channels

Glass-like dynamics of collective cell migration

Bacillus subtilis spreads by surfing on waves of surfactant

Spinodal Decomposition in a Model Colloid-Polymer Mixture in Microgravity

A Quantitative Analysis of Contractility in Active Cytoskeletal Protein Networks

Breakup of double emulsions in constrictions

Droplet-Based Microfluidic Platforms for the Encapsulation and Screening of Mammalian Cells and Multicellular Organisms

Real-Space Imaging of Nucleation and Growth in Colloidal Crystallization

Eutectic Gallium-Indium (EGaIn): A Liquid Metal Alloy for the Formation of Stable Structures in Microchannels at Room Temperature

Colloidosomes: Selectively Permeable Capsules Composed of Colloidal Particles

Optically Anisotropic Colloids of Controllable Shape

Polarization dependent Bragg diffraction and electro-optic switching of three-dimensional assemblies of nematic liquid crystal droplets

Topological Changes in Bipolar Nematic Droplets under Flow

Tetrahedral calcite crystals facilitate self-assembly at the air-water interface

Dewetting Instability during the Formation of Polymersomes from Block-Copolymer-Stabilized Double Emulsions

Self-assembled Shells Composed of Colloidal Particles: Fabrication and Characterization

Glioma Expansion in Collagen I Matrices: Analyzing Collagen Concentration-Dependent Growth and Motility Patterns

Amphiphilic Crescent-Moon-Shaped Microparticles Formed by Selective Adsorption of Colloids

Gravitational Stability of Suspensions of Attractive Colloidal Particles

Influence of Internal Capsid Pressure on Viral Infection by Phage Lambda

Monodisperse Emulsion Generation via Drop Break Off in a Coflowing Stream

Elasticity of dilatant particle suspensions during flow

Viscoelastic properties of oxide-coated liquid metals

Generation of Polymerosomes from Double-Emulsions

Yielding and Flow of Monodisperse Emulsions

Electric-field-induced capillary attraction between like-charged particles at liquid interfaces

Spontaneous Formation of Lipid Structures at Oil/Water/Lipid Interfaces

Dropspots: a picoliter array in a microfluidic device

Polymers fit for function Making emulsions drop by drop

Microfluidic Assembly of Homogeneous and Janus Colloid-Filled Hydrogel Granules

Corrugated interfaces in multiphase core-annular flow

Microfluidic Fabrication of Monodisperse Biocompatible and Biodegradable Polymersomes with Controlled Permeability

Droplet Microfluidics for Fabrication of Non-Spherical Particles

Buckling and Crumpling of Drying Droplets of Colloid-Polymer Suspensions

Physical forces during collective cell migration

Onset of Buckling in Drying Droplets of Colloidal Suspensions

Dripping, Jetting, Drops, and Wetting: The Magic of Microfluidics

Absolute Instability of a Liquid Jet in a Coflowing Stream

Fabrication of Monodisperse Toroidal Particles by Polymer Solidification in Microfluidics

Dynamics of Drying in 3D Porous Media

The pressure drop along rectangular microchannels containing bubbles

Electrostatic Charging Due to Separation of Ions at Interfaces: Contact Electrification of Ionic Electrets

Eutectic Gallium-Indium (EGaIn): A Liquid Metal Alloy for the Formation of Stable Structures in Microchannels at Room Temperature

Fabrication of Arrays of Metal and Metal Oxide Nanotubes by Shadow Evaporation

Interfacial instabilities in a microfluidic Hele-Shaw cell

Integrated Fabrication and Magnetic Positioning of Metallic and Polymeric Nanowires Embedded in Thin Epoxy Slabs

Basic Microfluidic and Soft Lithographic Techniques

Continuously tunable microdroplet-laser in a microfluidic channel

Fabrication of Micrometer-Scale, Patterned Polyhedra by Self-Assembly

Chemical Force Spectroscopy in Heterogeneous Systems: Intermolecular Interactions Involving Epoxy Polymer, Mixed Monolayers, and Polar Solvents

Surface Tension-Powered Self-Assembly of Microstructures—The State-of-the-Art

Self-Assembled Monolayers of Thiolates on Metals as a Form of Nanotechnology

Formation of droplets and bubbles in a microfluidic T-junction—scaling and mechanism of break-up