Navigation Links
Videos extract mechanical properties of liquid-gel interfaces
Date:1/23/2008

Blood coursing through vessels, lubricated cartilage sliding against joints, ink jets splashing on paperliving and nonliving things abound with fluids meeting solids. However important these liquid/solid boundaries may be, conventional methods cannot measure basic mechanical properties of these interfaces in their natural environments. Now, researchers at the National Institute of Standards and Technology (NIST) and the University of Minnesota have demonstrated a video method that eventually may be able to make measurements on these types of biological and industrial systems.*

Optical microrheologyan emerging tool for studying flow in small samplesusually relies on heat to stir up motion. Analyzing this heat-induced movement can provide the information needed to determine important mechanical properties of fluids and the interfaces that fluids form with other materials. However, when strong flows overwhelm heat-based motion, this method isn't applicable.

Motivated by this, researchers developed a video method that can extract optically basic properties of the liquid/solid interface in strong flows. The solid material they chose was a gel, a substance that has both solid-like properties such as elasticity and liquid-like properties such as viscosity (resistance to flow).

In between a pair of centimeter-scale circular plates, the researchers deposited a gel of polydimethylsiloxane (a common material used in contact lenses and microfluidics devices). Pouring a liquid solution of polypropylene glycol on the gel, they then rotated the top plate to create forces at the liquid/gel interface. The results could be observed by tracking the motion of styrene beads in the gel.

The researchers discovered that the boundary between the liquid and gel became unstable in response to mechanical noise (irregularities in the motion of the plates). Such noise occurs in real-world physical systems. Surprisingly, a small amount of this mechanical noise produced a lot of motion at the fluid/gel interface. This motion provided so much useful information that the researchers could determine the gels mechanical propertiesnamely its viscoelasticityat the liquid/gel interface.

The encouraging results from this model system show that this new approach could potentially be applied to determining properties of many useful and important liquid/solid interfaces. The NIST/Minnesota approach has possible applications in areas as diverse as speech therapy where observing the flow of air over vocal cords could enable noninvasive measures of vocal tissue elasticity and help clinicians detect problems at an early stage. Also, this research may help clarify specific plastics manufacturing problems, such as shear banding, in which flow can separate a uniformly blended polymer undesirably into different components.


'/>"/>

Contact: Ben Stein
bstein@nist.gov
301-975-3097
National Institute of Standards and Technology (NIST)
Source:Eurekalert  

Related biology news :

1. Bilberry extract -- can it help prevent certain cancers?
2. New mechanical insights into wound healing and scar tissue formation
3. Improving detection of nuclear smuggling goal of computer model of mechanical engineer
4. Weird water: Discovery challenges long-held beliefs about waters special properties
5. TRAP preserves genetic properties of popular geranium
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Videos extract mechanical properties of liquid-gel interfaces
(Date:11/17/2016)... Global Market Watch: Primarily supported by ... Banks and Academics) market is to witness a value of ... the highest Compounded Annual Growth Rate (CAGR) of 10.75% is ... analysis period 2014-2020. North America is ... Europe at 9.56% respectively. Report ...
(Date:11/16/2016)... Sensory Inc ., a Silicon ... consumer electronics, and VeriTran , a technology ... today announced a global partnership that will provide ... users of mobile banking and mobile payments solutions.  ... which requires no specialized biometric scanners, yet provides ...
(Date:11/15/2016)... Research and Markets has announced the addition ... report to their offering. ... The global ... from USD 6.21 Billion in 2016, growing at a CAGR of ... bioinformatics market is driven by the growing demand for nucleic acid ...
Breaking Biology News(10 mins):
(Date:12/9/2016)... ... December 09, 2016 , ... There’s a winning streak at Voxx ... Orange County Register, after winning the award last year as well. Employees nominate their ... and COO Daniel Vesely pointed to the tech company’s upbeat environment as a reason. ...
(Date:12/9/2016)... -- A platform of orthopedic device technologies developed by researchers ... to becoming viable options for repairing broken bones ... company from Philadelphia, PA. , ... absorbable bone fixation and regenerative repair technologies and ... company has leased space within the University City ...
(Date:12/8/2016)... Dec. 8, 2016  The Board of Directors of ... Western Pennsylvania,s only pure life sciences ... accordance with the succession plan developed by the Nominating ... today, James (Jim) F. Jordan is selected ... John W. Manzetti , who is elected to ...
(Date:12/8/2016)... ... December 08, 2016 , ... From wearable devices that can ... sports. On Thursday, December 15th a panel of entrepreneurs, innovators and a Philadelphia ... at a Smart Talk session. Smart Talk will run from 8:30 – 10:30 ...
Breaking Biology Technology: