Navigation Links
Columbia engineering team discovers graphene's weakness
Date:11/30/2010

New York, NY November 29, 2010 In 2008, experiments at The Fu Foundation School of Engineering and Applied Science at Columbia University established pure graphene, a single layer of graphite only one atom thick, as the strongest material known to mankind. This raised a question for Chris Marianetti, Assistant Professor in Columbia Engineering's Department of Applied Physics and Applied Mathematics: how and why does graphene break?

Using quantum theory and supercomputers, Marianetti has revealed the mechanisms of mechanical failure of pure graphene under tensile stress. In a paper recently accepted for publication in the journal Physical Review Letters, he shows that, when graphene is subject to strain equal in all directions, it morphs into a new structure which is mechanically unstable.

Marianetti says this failure mechanism is a novel soft-mode phonon instability. A phonon is a collective vibrational mode of atoms within a crystal, similar to a wave in a liquid. The fact that a phonon becomes "soft" under tensile strain means that the system can lower its energy by distorting the atoms along the vibrational mode and transitioning to a new crystalline arrangement. Under sufficient strain, graphene develops a particular soft-mode that causes the honeycomb arrangement of carbon atoms to be driven towards isolated hexagonal rings. This new crystal is structurally weaker, resulting in the mechanical failure of the graphene sheet.

"This is exciting on many different levels," Marianetti notes. "Soft modes were first recognized in the 1960s in the context of ferroelectric phase transitions, but they have never been directly linked to fracture. Typically, defects in a material will always cause failure to happen prematurely, but the pristine nature of graphene allows one to test our prediction. We have already outlined some interesting new experiments to directly observe our theoretical prediction of the soft mode."

Marianetti
'/>"/>

Contact: Holly Evarts
holly@engineering.columbia.edu
212-854-3206
Columbia University
Source:Eurekalert

Page: 1 2

Related biology technology :

1. OncoGenex Pharmaceuticals Named Life Sciences Company of the Year by LifeSciences British Columbia
2. Leading North American Emergency Medical Services Provider British Columbia Ambulance Service Selects NICE Inform for Improved Service
3. American Oriental Bioengineering Announces Participation in September Investor Conferences
4. Online Systems Engineering Master's Program Attracts Engineers from Fortune 500 Firms
5. NSF awards 14 materials research science and engineering centers
6. Genetic Engineering & Biotechnology News reports on growing role of molecular diagnostics
7. Genstruct Expands Team with New VP of Engineering
8. Engineering nanoparticles for maximum strength
9. American Oriental Bioengineering Completes Two Acquisitions
10. American Oriental Bioengineering, Inc. to Report Third Quarter 2008 Financial Results
11. American Oriental Bioengineering Announces Participation in November Investor Conferences
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/22/2015)... Selexis SA, a serial innovation company ... (RCBs) used for drug discovery to commercial manufacturing, announced ... Next-Generation Sequencing (NGS) data packages. The NGS ... by ensuring the integrity of the gene, validation of ...
(Date:1/22/2015)... , Jan. 22, 2015   GenoSpace , a precision ... tools to enable the broad use of genomic, imaging and ... the appointment of Michelle Munson , CEO of Aspera, ... Logo - http://photos.prnewswire.com/prnh/20150122/170713 ...
(Date:12/24/2014)... AUSTIN, Texas , Dec. 24, 2014  Vermillion, ... focused on gynecologic disease, announced today that the ... investors including Oracle Investment Management, Jack W. ... directors. Total proceeds were $10.5 million, before offering ...
(Date:12/24/2014)... 23, 2014 SoundConnect’s ... introduce cutting edge communication technology, provide continued education ... This webinar series demonstrates online communication features and ... web conferencing’s most innovative and powerful tools. , ...
Breaking Biology Technology:Selexis Generated Research Cell Banks Now Fully Sequenced Using Next-Generation Sequencing 2GenoSpace Expands Board with Appointment of Michelle Munson 2Vermillion Announces Closing of Equity Financing 2Vermillion Announces Closing of Equity Financing 3SoundConnect Launches Leading Edge Business Communications Webinar Series 2SoundConnect Launches Leading Edge Business Communications Webinar Series 3
... A source close to the toy industry has once again ... politicians. Heres what the good (and not-so-good) boys and girls ... Christmas morning. But they better not pout and they better ... were delivered down the chimney after midnight. , , Gov. ...
... in 1998, human embryonic stem cells were considered heralds of ... unlimited supply of cells and tissue of all kinds to ... in the glitz of the cells' potential to treat an ... that, when all is said and done, could match even ...
... decidedly hostile environment, the lowly tapeworm uses a chemical trick ... ,Capitalizing on that tapeworm chemistry, scientists at the University of ... the transit of drugs through the intestine, making them more ... only of more effective treatment, but also of lowering dosage ...
Cached Biology Technology:Unwrapping Political Perks for the Holidays 2Unwrapping Political Perks for the Holidays 3Stem Cells Illuminate Early Stages of Human Development 2Stem Cells Illuminate Early Stages of Human Development 3Tapeworm's Chemical Trick Could Make Drugs More Effective 2
(Date:12/22/2014)... 2014 Research and Markets ( http://www.researchandmarkets.com/research/fx4bg3/the_global ... "The Global Watermarking and Fingerprinting Markets" report ... http://photos.prnewswire.com/prnh/20130307/600769 This insight provides an ... fingerprinting markets. Watermarking aims to control and monitor ...
(Date:12/19/2014)... , Dec. 18, 2014  23andMe, Inc., the leading personal genetics ... fine-scale differences in genetic ancestry of individuals from across ... first arrived more than four hundred years ago, ... place for peoples from different continents. This study illuminates how ...
(Date:12/17/2014)...  HITLAB SM announced today its completion of a ... to current U.S. Food and Drug Administration (FDA) regulations. ... and smart phone application trials utilizing the highest principles ... is determined to improve global healthcare access, quality, and ...
Breaking Biology News(10 mins):The Global Watermarking and Fingerprinting Markets 223andMe Study Sketches Genetic Portrait of the United States 223andMe Study Sketches Genetic Portrait of the United States 323andMe Study Sketches Genetic Portrait of the United States 4HITLAB Completes GCP Audit for FDA Smart Device & App Compliance 2
... MURCIA, SPAINSalt can have drastic effects on the ... that salinity renders an about one-third of the world,s ... salinity can cause ion toxicity, osmotic stress, mineral deficiencies, ... stress can even cause plants to adjust their water ...
... of modern humans like more than 50,000 years ago? ... Stone Age engravings are the subjects of a good deal ... journal Science , an international team of researchers report ... could place the use of herbal medicines much earlier than ...
... growing in popularity as more growers turn to strip-till. However, ... worth. A new University of Illinois study revealed ... soybean. However, the results showed no difference in yield between ... corn, not soybean," said Fabian Fernandez, U of I assistant ...
Cached Biology News:Salt-tolerant crops show higher capacity for carbon fixation 2Earliest known bug-repellant plant bedding found at South African rock shelter 2Earliest known bug-repellant plant bedding found at South African rock shelter 3Earliest known bug-repellant plant bedding found at South African rock shelter 4Strip-till improves nutrient uptake and yield 2
ANTI S. GROUP AG:H...
This kit only detects beta-galactosidase activity at pH 6 in cultured cells andtissue sections. Beta-galactosidase activity at pH 6 ispresent only in senescent cells, and is not found inpresenescent...
2,4,6, Trinitrophenyl hapten is conjugated to lipopolysaccharide (LPS)....
... when you need to make your strain of ... Our services for preparing competent cells are comprehensive ... competent cell service offers: High ... turnaround Quality control performance testing ...
Biology Products: