Scientists are normal people just like us all. They do the same things and act just like us. Most of them speak foreign languages. Scientists aren't always stuck in their offices. They have lives outside of the labs too. Some like to do outdoor activities; others like to read or do things inside.http://www-ed.fnal.gov/projects/scientists/dans.html

To me, a scientist is bald and has hair coming out of the sides of his head. . . . Scientists live in their own world and the rest of society puts them there.

http://www.physik3.gwdg.de/~rgeisle/nld/blaf.html

Sound into Light

Sonoluminescence

http://www.scs.uiuc.edu/suslick/britannica.html

Applications of Ultrasound

•Enhancement of chemical reactions (sonocatalysis and sonochemistry)

•Cleaning•Medical procedures•Treatment of industrial liquid waste•Possible nuclear aspects?

Heterogeneous Sonochemistry

http://www.aeat.co.uk/sono/

Particle size reduction

http://rsrch.com/saturna/sonofusion.html

Titanium foil after sonication (true color)

MBSL versus SBSL• System of many

bubbles• Light emission

correlates to bubble collapse

• Multibubble systems drive heterogeneous sonochemistry

• System of one bubble driven by a resonant frequency

• Light emission correlates to minimum resonant bubble size

• More difficult to obtain

http://www.scs.uiuc.edu/suslick/images/sonolum.luminol.horn.jpg

http://mmae.iit.edu/communications/vectors/apr97/bubble.gif

Light emission of MB and SB systems is different

MBSL SBSL

MBSL Emission Spectra

Frequency dependence of SL intensity in aqueous solutions

The SL emission intensity is directly proportional to the atomic number of the noble gas saturated in the solution.

Other factors affect SL intensity

•pH of solutions doped with alkyl acids or akylamines

•Temperature of solutions (20-25° C most research data)

•Vapor pressure (SL intensity α 1/vapor pressure)

Model of bond cleavage/temperature due to

cavitational “hot-Spot”Energy release during cavitational collapse causes the chemical bonds to dissociate. Triply-bonded molecules such as N2 require higher temperatures for bond cleavage.

TESCSonicators

•Frequencies of about 20-40kHz

•Horn external to bath

•Not sealed•Large container

•Frequencies of up to 1MHz

•Horn Immersed in bath

•Sealed•Small container

Sonochemistry Equipment

Sonochemistry Equipment

http://www.scs.uiuc.edu/suslick/britannica.html

The End