Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Mechanoluminescence event yields novel emissions, reactions

09.05.2007
Researchers at the University of Illinois report that a new study of mechanoluminescence revealed extensive atomic and molecular spectral emission not previously seen in a mechanoluminescence event. The findings, which appear online this month in the Journal of the American Chemical Society, also include the first report of gas phase chemical reactions resulting from a mechanoluminescence event.
Mechanoluminescence is light generated when a crystal, such as sugar or quartz, is fractured by grinding, cleaving or via other mechanical means. Sir Francis Bacon wrote about this phenomenon as early as 1605. Others have used the effect to impress, if not enlighten, others.

"You may, when in the dark frighten simple people only by chewing lumps of sugar, and, in the meantime, keeping your mouth open, which will appear to them as if full of fire," Father Giambattista Beccaria wrote in "A Treatise Upon Artificial Electricity," in 1753.

Scientists believe mechanoluminescence occurs as a result of the generation of opposite charges along the fracture plane of an asymmetrical or impure crystal. When the charges recombine the surrounding gas is ionized and emits light.

Mechanoluminescence that results from simple grinding or cleavage of a crystal can be quite weak and difficult to study. Late last year, U. of I. chemistry professor Kenneth Suslick and graduate student Nathan Eddingsaas reported in the journal Nature that a new technique, the sonication of crystal slurries, produced a much more intense mechanoluminescence than grinding. Sonication, the use of sound energy to agitate particles or other substances, causes high intensity collisions of crystal particles in liquid slurries.

The resulting mechanoluminescence is an order of magnitude brighter than that produced by grinding.

Sonication of liquids causes acoustic cavitation: the formation, growth and implosion of bubbles. This generates tremendous heat, pressure and shockwaves within the liquid that can exceed the speed of sound. Crystal particles suspended in a sonicated liquid collide and fracture, causing intense mechanoluminescence.

The new study involved the sonication of a slurry of recorcinol
(sugar) crystals in the liquid paraffin, dodecane. When nitrogen or oxygen was bubbled through the sonicated slurry, the resulting emission spectrum was more than a thousand time more intense than that produced by grinding. The researchers also saw emission lines not previously reported in a mechanoluminescence event. These peaks on the mechanoluminescence spectra are evidence of gas phase chemical reactions during the event.

"When oxygen is present, chemical reactions take place that are similar to those that occur in the production of diamond films using an electrical discharge," Suslick said. "The intense mechanoluminescence and chemical reactions produced by ultrasound give us a better understanding of mechanoluminescence, mechanochemistry and the effect of ultrasound on solids within a liquid."

Editor's note: To reach Kenneth Suslick, call 217-333-2794; e-mail:
ksuslick@uiuc.edu.

News Bureau | University of Illinois
Further information:
http://www.news.uiuc.edu/news/07/0508sonication.html

Further reports about: Emission chemical reaction mechanoluminescence produced

More articles from Life Sciences:

nachricht Building a brain, cell by cell: Researchers make a mini neuron network (of two)
23.05.2018 | Institute of Industrial Science, The University of Tokyo

nachricht Research reveals how order first appears in liquid crystals
23.05.2018 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

Im Focus: Dozens of binaries from Milky Way's globular clusters could be detectable by LISA

Next-generation gravitational wave detector in space will complement LIGO on Earth

The historic first detection of gravitational waves from colliding black holes far outside our galaxy opened a new window to understanding the universe. A...

Im Focus: Entangled atoms shine in unison

A team led by Austrian experimental physicist Rainer Blatt has succeeded in characterizing the quantum entanglement of two spatially separated atoms by observing their light emission. This fundamental demonstration could lead to the development of highly sensitive optical gradiometers for the precise measurement of the gravitational field or the earth's magnetic field.

The age of quantum technology has long been heralded. Decades of research into the quantum world have led to the development of methods that make it possible...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

 
Latest News

Research reveals how order first appears in liquid crystals

23.05.2018 | Life Sciences

Space-like gravity weakens biochemical signals in muscle formation

23.05.2018 | Life Sciences

NIST puts the optical microscope under the microscope to achieve atomic accuracy

23.05.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>