Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Flowing Structures in Soft Crystals

Intriguing structures formed by tiny particles floating in liquids. (Copyright: Vienna University of Technology)
Intriguing structures formed by tiny particles floating in liquids. (Copyright: Vienna University of Technology)

Abstract:
A liquid does not have to be a disordered bunch of particles: A team of researchers at Vienna University of Technology (TU Vienna) and the University of Vienna has discovered intriguing structures formed by tiny particles floating in liquids. Under mechanical strain, particle clusters in liquids can spontaneously form strings and dramatically alter the properties of the liquid.

Flowing Structures in Soft Crystals

Vienna, Austria | Posted on August 8th, 2011

What is common to blood, ink and gruel? They are all liquids in which tiny particles are suspended - so called "colloids". In some of these liquids, the particles form groups (clusters), which form regular structures, much like atoms in a crystal. A team of researchers from TU Vienna and Vienna University has now managed to study the remarkable properties of these crystal-like substances in computer simulations. Under mechanical strain, the crystalline pattern can change into a different structure, or it can vanish completely. The researchers anticipate a broad range of practical applications for these effects. The results of their calculations have now been published in the scientific journal "Physical Review Letters".

Regular Structures in Liquids
If small particles accumulate, they can form clusters. Within a cluster, the particles may overlap and mingle, similar to a densely packed shoal of eels, gliding past each other. Remarkably, these clusters are not situated at random positions, but they spontaneously form a regular structure - a "cluster crystal". The distance between two neighboring clusters is constant. "Increasing the density of particles adds more and more particles to each cluster - but the distance between them stays the same", says Arash Nikoubashman, PhD-student at TU Vienna. He made the calculations together with Professor Gerhard Kahl (Institute for Theoretical Physics, TU Vienna) and Professor Christos Likos (University of Vienna).

Crystal Structure Turning into Strings
"Previous results had already led us to believe that these particles could exhibit strange behavior under certain external conditions", the physicists explain. And their hopes were not unfounded: in computer simulations they managed to calculate how the crystal-like structure behaves under mechanical strain that causes shears stress - which means that surfaces within the liquid are shifted relative to each other. At first, the crystal structure starts to melt, the connections between the clusters are broken. From these molten particle clusters, a new regular order starts to emerge spontaneously. Long, straight strings of particle are formed, neatly aligned in parallel.

Thin and Thick
While these strings are created, the liquid gets thinner, its viscosity decreases. This is due to the strings being able to slide relative to one another. If the material is subject to even more strain, the strings break up too, a "molten" unstructured ensemble of particle clusters remains, and the viscosity of the liquid increases again. More and more particles are washed away from their original positions and inhibit the flow. This behavior is the same for all kinds of cluster crystals. With a simple theoretical model, the critical strain, at which the ordered structure vanishes completely, can be predicted very accurately.

Under shear strain, crystals made of soft, penetrable particles can exhibit new kinds of self-organization. Geometric structures emerge, governed by the kind of forces acting between the particles. This research in the field of "soft matter" in the micro- and nanometer regime is not only interesting from a theoretical point of view. These materials play an important role in our everyday life - such as blood or large biopolymers like DNA. They are important in biotechnology, and also in petrochemistry and pharmacology - wherever tailor-made nano materials are being used. A liquid which can change its viscosity under mechanical stress promises a broad spectrum of possible applications - ranging from vibration dampers to protective clothing.

####

For more information, please click here

Contacts:
Scientific contacts
Univ.-Prof. Dipl.-Ing. Dr. Christos Likos
Computational Physics
University of Vienna
1090 Wien, Sensengasse 8
T +43-1-4277-732 30


Arash Nikoubashman
Vienna University of Technology
Wiedner Hauptstra▀e 8-10
T +43-1-58801-136 31


Press contact
Mag. Veronika Schallhart
Public Relations
University of Vienna
1010 Vienna, Dr.-Karl-Lueger-Ring 1
T +43-1-4277-175 30
M +43-664-60277-175 30

Copyright © University of Vienna

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Discoveries

How to maximize the superconducting critical temperature in a molecular superconductor: International team led by Tohoku University opens new route for discovering high Tc superconductors April 19th, 2015

Optical resonance-based biosensors designed for medical applications April 18th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Materials/Metamaterials

How to maximize the superconducting critical temperature in a molecular superconductor: International team led by Tohoku University opens new route for discovering high Tc superconductors April 19th, 2015

The National Science Foundation names engineering researcher Andrea Al˙ its Alan T. Waterman awardee for 2015: Al˙ is a pioneer in the field of metamaterials who has developed "cloaking" technology to make objects invisible to sensors April 16th, 2015

Cobalt film a clean-fuel find: Rice University discovery is efficient, robust at drawing hydrogen and oxygen from water April 15th, 2015

Combined effort for structural determination April 15th, 2015

Announcements

How to maximize the superconducting critical temperature in a molecular superconductor: International team led by Tohoku University opens new route for discovering high Tc superconductors April 19th, 2015

Iranian Foodstuff, Agricultural Industries Welcome Nanotechnology Packaging Bags April 18th, 2015

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Dais Analytic Corporation Appoints Eliza Wang to Board of Directors: Company's Newest Director Brings Expertise in Commercial and Legal Matters Both in the United States and China; Joins on the Heels of Successful Business Development Trade Mission to China April 18th, 2015

Textiles/Clothing

Nanocomposites Play Effective Role in Production of Smart Fibers April 18th, 2015

Inkjet-printed liquid metal could bring wearable tech, soft robotics April 8th, 2015

FibeRio and VF Corporation Form Strategic Partnership to Lead the Apparel and Footwear Markets in Nanofiber Technology April 8th, 2015

Scientists discover gecko secret March 16th, 2015

Nanobiotechnology

Protein Building Blocks for Nanosystems: Scientists develop method for producing bio-based materials with new properties April 17th, 2015

Study shows novel pattern of electrical charge movement through DNA April 14th, 2015

UAB researchers develop a harmless artificial virus for gene therapy April 8th, 2015

Pavel Levkin Is Granted Heinz Maier-Leibnitz Prize April 8th, 2015

Research partnerships

Beyond the lithium ion -- a significant step toward a better performing battery April 18th, 2015

Light in a spin: Researchers demonstrate angular accelerating light April 15th, 2015

Graphene pushes the speed limit of light-to-electricity conversion: Researchers from ICFO, MIT and UC Riverside have been able to develop a graphene-based photodetector capable of converting absorbed light into an electrical voltage at ultrafast timescales April 14th, 2015

Scientists create invisible objects without metamaterial cloaking April 14th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE