Monday, January 23, 2006

The dream of free-energy is still alive!

Get out your teleporting suit Rachna!
 

Science News Online

Thermonuclear Squeeze: Altered method extends bubble-fusion claim

Peter Weiss

A technique that some scientists claim generates thermonuclear fusion in a benchtop apparatus works even without its controversial neutron trigger. So say the researchers who, since 2002, have reported that nuclear-fusion reactions can occur in a vat of chilled solvent agitated by ultrasound (SN: 3/6/04, p. 149: Available to subscribers at http://www.sciencenews.org/articles/20040306/fob5.asp). If this method of sparking fusion proves to be valid—a big if, critics insist—it could lead to a remarkably simple, cheap, inexhaustible power source.

Fusion reactions take place in the vat because clusters of bubbles form and then violently collapse, explains nuclear engineer and team leader Rusi P. Taleyarkhan of Purdue University in West Lafayette, Ind. A neutron or another energetic particle triggers a bubble to form in a low-pressure trough of the ultrasound waves, he says. Then, high pressure from the wave crushes the orb to an enormous density and temperature that fuse some atomic nuclei of the bubble's gas.

Taleyarkhan and his colleagues have measured neutron emissions as a sign of fusion reactions. Because the group had used neutron pulses to trigger the process, other researchers have been skeptical of its neutron readings.

In an upcoming Physical Review Letters, Taleyarkhan's team presents evidence of fusion in bubbles initiated by a uranium-based trigger that emits alpha particles instead of neutrons. "We got away from the idea of using neutrons to produce neutrons," Taleyarkhan notes.

Nonetheless, the findings still face intense skepticism. Criticisms range from doubts about experimental procedures to quarrels with interpretations of the data. "I simply do not find the results significant and/or believable," comments physicist Dan Shapira of Oak Ridge (Tenn.) National Laboratory.

Critics note that Taleyarkhan's team admits in its report that its experimental outcomes vary greatly, many of them producing no evidence of fusion. Yet to D. Felipe Gaitan of Impulse Devices in Grass Valley, Calif., the uneven outcomes are encouraging. They "could explain our inability, and that of other researchers so far, to replicate [Taleyarkhan's] results consistently," says Gaitan. Impulse Devices plans to commercialize bubble fusion.

Lawrence A. Crum of the University of Washington in Seattle says that the new work "increases the credibility" of bubble fusion. But "unless it's reproduced in someone else's lab, I'm not going to believe it," he adds.

Taleyarkhan claims that his team's findings were independently verified last year by other Purdue researchers, whom he guided. Other physicists are unconvinced.

A welcome consequence of the latest results, Crum adds, is that other researchers should find the uranium-based triggering method easier to reproduce than the neutron one. So, he says, the new work "is an important step toward determining if the results of Rusi's experiments are true."


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References:

Shapiro, D., and M. Saltmarsh. 2002. Nuclear fusion in collapsing bubbles—is it there? An attempt to repeat the observation of nuclear emissions from sonoluminescence. Physical Review Letters 89(Sept. 2):104302. Abstract available at http://link.aps.org/abstract/PRL/v89/e104302.

Taleyarkhan, R.P., et al. In press. Nuclear emissions during self-nucleated acoustic cavitation. Physical Review Letters.

Taleyarkhan, R.P., et al. 2004. Additional evidence of nuclear emissions during acoustic cavitation. Physical Review E 69():036109. Abstract available at http://dx.doi.org/10.1103/PhysRevE.69.036109.

Taleyarkhan, R.P., et al. 2002. Evidence for nuclear emissions during acoustic cavitation. Science 295(March 8):1868-1873. Available at http://www.sciencemag.org/cgi/content/full/295/5561/1868.

Xu, Y., and A. Butt. 2005. Confirmatory experiments for nuclear emissions during acoustic cavitation. Nuclear Engineering and Design 235:1317-1324.

Further Readings:

Weiss, P. 2005. Brutal bubbles: Collapsing orbs rip apart atoms. Science News 167(March 5):147. Available at http://www.sciencenews.org/articles/20050305/fob1.asp.

______. 2004. Bubble fusion: Once-maligned claim rebounds. Science News 165(March 6):149. Available to subscribers at http://www.sciencenews.org/articles/20040306/fob5.asp.

______. 2002. Violent chemistry saps sonobubble energy. Science News 162(Aug. 24):125. Available to subscribers at http://www.sciencenews.org/articles/20020824/note15.asp.

______. 2002. Star in a jar? Hints of nuclear fusion found—maybe. Science News 161(March 9):147. Available at http://www.sciencenews.org/articles/20020309/fob1.asp.

Sources:

Lawrence A. Crum
Center for Industrial and Medical Ultrasound
Applied Physics Laboratory
University of Washington
1013 NE 40th Street
Seattle, WA 98105

D. Felipe Gaitlin
Impulse Devices, Inc.
Grass Valley Corporate & Research Office
13366 Grass Valley Avenue, Unit H
Grass Valley, CA 95945

Dan Shapira
Oak Ridge National Laboratory
P.O. Box 2008
Mailstop Code 6368
Oak Ridge, TN 37831-6368

Rusi P. Taleyarkhan
School of Nuclear Engineering
400 Central Drive
Purdue University
W. Lafayette, IN 47907-2017



http://www.sciencenews.org/articles/20060121/fob7.asp

From Science NewsVol. 169, No. 3, Jan. 21, 2006, p. 38.

Copyright (c) 2006 Science Service. All rights reserved.

Wednesday, January 18, 2006

An emerging emergent?

Surely someone has used that before, but I haven't so I did. Joanna will be so proud of me, as I have attended my first "emergent" (though they pronounce it "e-mergent" not "m-ergent" like you, but it is Iowa after all) meeting, or I'm not sure what to call it. So I just thought I would write about it.

Because I am a sap...

"I wish I could remember that first day,
First hour, first moment of your meeting me,
If dim or bright the season, it might be
Summer or winter for aught I can say;
So unrecorded did it slip away,
So blind was I to see and to foresee,
So dull to mark the budding of my tree
That would not blossom yet for many a May.
If only I could recollect it, such
A day of days! I let it come and go
As traceless as a thaw of bygome snow;
It seemed to mean so little, meant so much;
If only I could now recall that touch,
First touch of hand in hand-did one but know!

- "The First Day" by Christina Rossetti

For Joanna...

"We are all strangers in a strange land, longing for home, but not quite knowing what or where home is. We glimpse it sometimes in our dreams, or as we turn a corner, and suddenly there is a strange, sweet familiarity that vanishes almost as soon as it comes." - Madeleine L'Engle (please read her sci-fi books)

Friday, January 13, 2006

Some of my favorite websites

www.WebElements.com - an online periodic table, but not just any online periodic table, as this one has funny cartoons with some of the elements! Two that made me laugh! (yes, I am as geeky as you think I am)
















www.BlackMask.com - FREE books online! All pre
http://www.adobe.com/epaper/ebooks/ebookmall/main.html - Another site that tells you where to find free books!
www.ScienceNews.org - They definitely have some presuppositions about certain topics (for example, they tend to side with large corporation food industry) so you have to read carefully to see where they are basing their articles on opinion rather than truth, but somewhat interesting nonetheless.
www.Boundless.org - Relevant articles about culture & life
www.NashBar.com - a very good place to buy bike things
www.Oriland.com - fun origami site




Monday, January 02, 2006

Making money with your blog?

I'm sure all of the real bloggers know about this already, but did you know you can make money on your blog by placing ads?  (see: http://help.blogger.com/bin/answer.py?answer=1217).  First, I wonder if this might be annoying to the 1 or 2 people that actually visit my blog.  But then then I think it would be neat to make money, but then I would be supporting materialism/commercialism/blah.  Hmmm.  So something I haven't thought of before, have you?
 
 

Congratulations to Josephina!

As she has received an award for best blog of the year :)