. Space Industry and Business News .




.
TIME AND SPACE
A study describes liquid water diffusion at molecular level
by Staff Writers
Granada, Spain (SPX) Mar 01, 2012

Potential arrangement of 12 water molecules and their HBs within the cooperative 1nm region.

Researchers at the universities of Granada and Barcelona have described for the first time the diffusion of liquid water through nanochannels in molecular terms; nanochannels are extremely tiny channels with a diameter of 1-100 nanometers that scientists use to study the behavior of molecules (nm. a unit of length in the metric system equal to one billionth of a meter that is used in the field of nanotechnology).

This study might have an important impact on water desalinization and filtration methods. Two articles published in Science state that the introduction of graphene membranes and carbon nanolayers will revolutionize water desalinization and filtration processes, as water diffuses rapidly through these materials when their pores are 1nm in diameter.

Liquid water exhibits a range of unusual properties that other chemical compounds do not have: up to 65 abnormalities. Some of these abnormalities have been known for 300 years, as the fact that water expands below 4 degrees C.

Many of the abnormalities found in water have a dynamic nature -e.g. water molecules move faster as density increases-, as a result of the properties of the hydrogen bond networks that form between water molecules; hydrogen bonds lead to the formation of tetrahedral structures wherein a central atom is located at the center with four molecules located at the corners.

However, this geometrical structure changes with pressure and temperature and, until now, changes in the molecular structure and properties of liquid water had not been described.

A Mystery to Solve
Particularly confusing are the results on the diffusion of water confined between two hydrophobic plates. Neither experiments nor computer-based models have clarified whether confinement increases or reduces the mobility of water molecules. However, it seems that the mobility of water molecules relies on ducts having a diameter above or below 1nm.

In a study published in the prestigious journal Physical Review, professors Francisco de los Santos Fernandez (University of Granada) and Giancarlo Franzese (University of Barcelona) described the behavior of water confined between two hydrophobic plates.

In their study, Franzese and Fernandez used models to demonstrate that the diffusion of nanoconfined water is unusually fast, as a result of the competition between the formation and breaking of hydrogen bonds, and the free volume available for cooperative molecule rearrangement.

In nanochannels above 1 nm in diameter, macroscopic diffusion of water only occurs if there is a cooperative rearrangement of molecules, which leads to HB breaking within a cooperative region of 1nm in size. On the other hand, diffusion increases in nanochannels below 1 nm, as fewer HBs need to be broken.

Thus, this study proves that the interplay between hydrogen bond breaking and cooperative rearranging within regions of 1-nm determine the macroscopic properties of water.

Research Paper

Related Links
University of Granada
Understanding Time and Space




.
.
Get Our Free Newsletters Via Email
...
Buy Advertising Editorial Enquiries






.

. Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle



TIME AND SPACE
Scientists score victory over uncertainty in quantum physics measurements
Atlanta GA (SPX) Feb 29, 2012
Most people attempt to reduce the little uncertainties of life by carrying umbrellas on cloudy days, purchasing automobile insurance or hiring inspectors to evaluate homes they might consider purchasing. For scientists, reducing uncertainty is a no less important goal, though in the weird realm of quantum physics, the term has a more specific meaning. For scientists working in quantum phys ... read more


TIME AND SPACE
VTT scientists revise the 60-year-old definition of surface tension on solids

Radical new 'focus later' camera begins shipping

IBM takes giant step to faster, quantum computers

Tech giants get lecture on perils of gadget worship

TIME AND SPACE
Raytheon's US Air Force Satellite Terminal Achieves Two Critical Milestones

Northrop Grumman Airborne Network Demonstrates Tactical Potential at Army Integration Exercise

Lockheed Martin Delivers Second AEHF Satellite To U.S. Air Force For Upcoming Launch

United Launch Alliance Atlas V Launches Mobile User Objective System-1 Mission

TIME AND SPACE
SwRI and XCOR agree to pioneering research test flight missions

Rocket launches from Poker Flat Research Range

Private rocket assembled for space launch

Ariane 5 readied for dual-satellite launch fpr Asia-Pacific telco

TIME AND SPACE
LightSquared Undertakes Search for New CEO

Galileo on the ground reaches some of Earth's loneliest places

China launches 11th satellite for independent navigation system

Chinese province school buses to have GPS

TIME AND SPACE
Hong Kong Airlines may cancel A380 order: report

ISRO bets on satellite navigation for aviation services

Boeing to sell ten 777s to China Southern

Aircraft of the future could capture and re-use some of their own

TIME AND SPACE
Solving a Spintronic Mystery

Transforming computers of the future with optical interconnects

Penn Researchers Build First Physical "Metatronic" Circuit

Single-atom transistor is end of Moore's Law; may be beginning of quantum computing

TIME AND SPACE
Facility for Climate and Environmental Monitoring from Space

Google Street View to launch in Botswana

NASA Map Sees Earth's Trees In A New Light

NASA Satellite Finds Earth's Clouds are Getting Lower

TIME AND SPACE
Mobile industry eyes savings by recycling

Ship captain pleads guilty over N. Zealand oil spill

China orders more accurate air-quality measure

EU takes France to court over nitrates water pollution


Memory Foam Mattress Review

Newsletters :: SpaceDaily Express :: SpaceWar Express :: TerraDaily Express :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

.

The content herein, unless otherwise known to be public domain, are Copyright 1995-2012 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement