Featured Research

from universities, journals, and other organizations

Fundamental property of how water and other liquids move at different temperatures

Date:
January 20, 2011
Source:
Massachusetts Institute Of Technology
Summary:
In a finding that has been met with surprise and some controversy in the scientific community, researchers have discovered a basic property that governs the way water and many other liquids behave as their temperature changes.

In a finding that has been met with surprise and some controversy in the scientific community, researchers at MIT and elsewhere have discovered a basic property that governs the way water and many other liquids behave as their temperature changes.
Credit: Copyright Michele Hogan

In a finding that has been met with surprise and some controversy in the scientific community, researchers at MIT and elsewhere have discovered a basic property that governs the way water and many other liquids behave as their temperature changes.

Liquids have long been known to exhibit a rapid change in properties near a point called the glass transition temperature, where the viscosity of the liquid -- its "thickness," or resistance to flow -- becomes very large. But MIT professor Sow-Hsin Chen and his co-researchers have found a different transition point at a temperature about 20 to 30 percent higher, which they call the dynamic crossover temperature. This temperature may be at least as important as the glass transition temperature, and the viscosity at the dynamic crossover temperature seems to have a universal value for a large class of liquids (called glass-forming liquids) that includes such familiar substances as water, ammonia and benzene.

At this new transition temperature, "all the transport properties of the liquid state change drastically," Chen says. "Nobody realized this universal property of liquids before." The work, carried out by physics professor Francesco Mallamace of the University of Messina, Italy (who is a research affiliate at MIT) and four of his students from Messina, along with Chen, an MIT professor emeritus of nuclear science and engineering, and Eugene Stanley, a physics professor at Boston University, was published on Dec. 28 in the Proceedings of the National Academy of Sciences.

This is very basic research and Chen says it is too early to predict what practical applications this knowledge could produce. "We can only speculate," he says, because "this is so new that real practical applications haven't really surfaced." But he points out that one of the most widely used building materials in the world, concrete, flows as a liquid-like cement paste during construction, and a better ability to understand its process of transition to solid form might be significant for improving its durability or other characteristics.

Controversial finding

The team had previously published their findings about the new transition temperature in water, but the new work extends this to the whole class of liquids. While the findings remain somewhat controversial, Chen says that last month an international symposium devoted to the study of this phenomenon was held in Florence, Italy involving about 50 scientists from various nations.

Benjamin Widom, an emeritus professor of chemistry at Cornell University, says that the researchers' demonstration of the universality of this crossover phenomenon and the fact that the liquids studied all show roughly the same level of viscosity at their crossover point "is striking," and adds that "These observations are certain to arouse much interest among those who work in the field, and perhaps even controversy because they contradict long-accepted ideas."

Liquids become much more viscous as they approach their freezing temperature -- that is, they begin to move less like water and more like honey. But the exact progression of this transition is difficult to measure, so the details are still poorly understood. The new research draws on published studies detailing the behavior of 84 different liquids, and the researchers found that a fresh analysis of the data, along with their own experimental work on water, shows a previously unrecognized universal property they all share in terms of how their viscosity and other characteristics change with temperature.

"Measuring viscosity is a very tedious process," Chen says, and measuring how it changes over tiny increments of temperature is even more difficult. But Chen and his colleagues found that they were able to measure relaxation time of water -- which is directly proportional to its viscosity -- using a state-of-the-art instrument at the National Institute of Standards and Technology in Washington that shoots neutrons at the material. "We discovered we can measure relaxation time very effectively with this instrument," Chen said, and they have been carrying out such measurements over the last several years.

The research was supported in U.S. by grants from the U.S. Department of Energy and the National Science Foundation and in Italy from the Research Programs of National Interest.


Story Source:

The above story is based on materials provided by Massachusetts Institute Of Technology. Note: Materials may be edited for content and length.


Journal Reference:

  1. F. Mallamace, C. Branca, C. Corsaro, N. Leone, J. Spooren, S.-H. Chen, H. E. Stanley. Transport properties of glass-forming liquids suggest that dynamic crossover temperature is as important as the glass transition temperature. Proceedings of the National Academy of Sciences, 2010; 107 (52): 22457 DOI: 10.1073/pnas.1015340107

Cite This Page:

Massachusetts Institute Of Technology. "Fundamental property of how water and other liquids move at different temperatures." ScienceDaily. ScienceDaily, 20 January 2011. <www.sciencedaily.com/releases/2011/01/110119160205.htm>.
Massachusetts Institute Of Technology. (2011, January 20). Fundamental property of how water and other liquids move at different temperatures. ScienceDaily. Retrieved September 30, 2014 from www.sciencedaily.com/releases/2011/01/110119160205.htm
Massachusetts Institute Of Technology. "Fundamental property of how water and other liquids move at different temperatures." ScienceDaily. www.sciencedaily.com/releases/2011/01/110119160205.htm (accessed September 30, 2014).

Share This



More Matter & Energy News

Tuesday, September 30, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Do Video Games Trump Brain Training For Cognitive Boosts?

Do Video Games Trump Brain Training For Cognitive Boosts?

Newsy (Sep. 29, 2014) More and more studies are showing positive benefits to playing video games, but the jury is still out on brain training programs. Video provided by Newsy
Powered by NewsLook.com
CERN Celebrates 60 Years of Science

CERN Celebrates 60 Years of Science

Reuters - Business Video Online (Sep. 29, 2014) CERN, the European Organisation for Nuclear Research, celebrates 60 years of bringing nations together through science. As Joanna Partridge reports from inside the famous science centre it's also planning to turn the Large Hadron Collider particle accelerator back on after an upgrade. Video provided by Reuters
Powered by NewsLook.com
This 'Invisibility Cloak' Is Simpler Than Most

This 'Invisibility Cloak' Is Simpler Than Most

Newsy (Sep. 28, 2014) Researchers from the University of Rochester have created a type of invisibility cloak with simple focal lenses. Video provided by Newsy
Powered by NewsLook.com
New Corvette Can Secretly Record Convos And Get You Arrested

New Corvette Can Secretly Record Convos And Get You Arrested

Newsy (Sep. 28, 2014) The 2015 Corvette features valet mode – which allows the owner to secretly record audio and video – but in many states that practice is illegal. Video provided by Newsy
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins