Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Explosives at the microscopic scale produce shocking results

Abstract:
U.S. troops blew up enemy bridges with explosives in World War II to slow the advance of supplies or enemy forces.

Explosives at the microscopic scale produce shocking results

LIVERMORE, CA | Posted on December 10th, 2007

In modern times, patrollers use explosives at ski resorts to purposely create avalanches so the runs are safer when skiers arrive.

Other than creating the desired effect (a destroyed bridge or avalanche), the users didn't exactly know the microscopic details and extreme states of matter found within a detonating high explosive.

In fact, most scientists don't know what happens either.

But researchers from Lawrence Livermore National Laboratory and the Massachusetts Institute of Technology have created the first quantum molecular dynamics simulation of a shocked explosive near detonation conditions, to reveal what happens at the microscopic scale.

What they found is quite riveting: The explosive, nitromethane, undergoes a chemical decomposition and a transformation into a semi-metallic state for a limited distance behind the detonation front.

Nitromethane is a more energetic high explosive than TNT, although TNT has a higher velocity of detonation and shattering power against hard targets. Nitromethane is oxygen poor, but when mixed with ammonium nitrate can be extremely lethal, such as in the bombing of the Alfred P. Murrah Federal Building in Oklahoma City.

"Despite the extensive production and use of explosives for more than a century, their basic microscopic properties during detonation haven't been unraveled," said Evan Reed, the lead author of a paper appearing in the Dec. 9 online edition of the journal, Nature Physics. "We've gotten the first glimpse of the properties by performing the first quantum molecular dynamics simulation."

In 2005 alone, 3.2 billion kilograms of explosives were sold in the United States for a wide range of applications, including mining, demolition and military applications.

Nitromethane is burned as a fuel in drag racing autos, but also can be made to detonate, a special kind of burning in which the material undergoes a much faster and far more violent type of chemical transformation. With its single nitrogen dioxide (NO2) group, it is a simple representative version of explosives with more NO2 groups.

Though it is an optically transparent, electrically insulating material, it undergoes a shocking transformation: It turns into an optically reflecting, nearly metallic state for a short time behind the detonation shock wave front.

But further behind the wave front, the material returns to being optically transparent and electrically insulating.

"This is the first observation of this behavior in a molecular dynamics simulation of a shocked material," Reed said. "Ultimately, we may be able to create computer simulations of detonation properties of new, yet-to-be synthesized designer explosives."

Other Livermore researchers include M. Riad Manaa, Laurence Fried, Kurt Glaesemann and J.D. Joannopoulos of MIT.

The work was funded by the Laboratory Directed Research and Development program.

####

About Lawrence Livermore National Laboratory
Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.

Contacts:
Anne M. Stark
Phone: (925) 422-9799

Copyright © Lawrence Livermore National Laboratory

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

Nature paper by Schlumberger researchers used photothermal based nanoscale IR spectroscopy to analyze heterogeneous process of petroleum generation January 23rd, 2018

Researchers use sound waves to advance optical communication January 22nd, 2018

Piecework at the nano assembly line: Electric fields drive nano-motors a 100,000 times faster than previous methods January 22nd, 2018

Thanks for the memory: NIST takes a deep look at memristors January 20th, 2018

Announcements

Nature paper by Schlumberger researchers used photothermal based nanoscale IR spectroscopy to analyze heterogeneous process of petroleum generation January 23rd, 2018

New filters could enable manufacturers to perform highly-selective chemical separation January 23rd, 2018

Researchers use sound waves to advance optical communication January 22nd, 2018

Piecework at the nano assembly line: Electric fields drive nano-motors a 100,000 times faster than previous methods January 22nd, 2018

Military

Researchers use sound waves to advance optical communication January 22nd, 2018

New Method Uses DNA, Nanoparticles and Top-Down Lithography to Make Optically Active Structures: Technique could lead to new classes of materials that can bend light, such as for those used in cloaking devices January 18th, 2018

New exotic phenomena seen in photonic crystals: Researchers observe, for the first time, topological effects unique to an “open” system January 12th, 2018

Nanotube fibers in a jiffy: Rice University lab makes short nanotube samples by hand to dramatically cut production time January 11th, 2018

Quantum nanoscience

New oxide and semiconductor combination builds new device potential: Researchers integrated oxide two-dimensional electron gases with gallium arsenide and paved the way toward new opto-electrical devices January 10th, 2018

Columbia engineers create artificial graphene in a nanofabricated semiconductor structure: Researchers are the first to observe the electronic structure of graphene in an engineered semiconductor; finding could lead to progress in advanced optoelectronics and data processing December 13th, 2017

Enhancing the quantum sensing capabilities of diamond: Shooting electrons at diamonds can introduce quantum sensors into them November 24th, 2017

Quantum optics allows us to abandon expensive lasers in spectroscopy: Lomonosov Moscow State University scientists have invented a new method of spectroscopy November 21st, 2017

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