I wake up scheming


Casual tee prevents casualties
April 6, 2010, 2:41 pm
Filed under: engineering your doom, evil biology | Tags: , , ,

The first thing anybody will tell you about raising bloodthirsty radioactive gila monsters to guard your subterranean lair (aside from “that’s madness, Dr. Rocket, they’ll tear you to bits!”) is that you’ve got to suit up: layer upon layer of bulky, unflattering body armor to make sure that the Gila monster doesn’t poison you with its deadly venom.  And that armor doesn’t breathe at all.

But wait!  Thanks to some new research from the University of South Carolina, the roly-poly lizard-keeper look may soon be a thing of the past.  Dr. Xiaodong Li has found that an ordinary cotton T-shirt doped with boron can turn into a material comparable to the armor used on tanks.

The process is simple, too – nothing you can’t do at home, assuming you live in a well-stocked underground laboratory. All you have to do is preheat your oven to 2012 degrees Fahrenheit, dip the tees in a boron solution, and bake (in argon gas, to keep the shirts from burning) until the cotton fibers turn into carbon fibers and bond with the boron to create boron carbide.  Remove from heat, cool on wire rack until wearable, and then sport your spiffy new duds anywhere you think you might get ripped to shreds by venomous beasts.

Unfortunately, the heavy-duty tees are far from being ready for me to wear to the Gila monster pit (or for Dr. Li’s original intent: as body armor for armed forces or police).  But early results are already lighter and stretchier than the presently available boron carbide plate body armor.  And when you’re training any sort of man-eating monster, maneuverability is key, so let’s hope that Dr. Li’s research gets us somewhere.



Mine ice have seen the glory

© D Sharon Pruitt

Anybody who has ever made a wish on the first snowflake of a childhood winter has probably dreamed of someday being able to freeze their enemies using a high-powered laser.  And that day is now a little closer, thanks to some arresting new research from the laboratory of Mansoor Sheik-Bahae of the University of New Mexico (published in the January 2010 issue of the Journal of Nature-Photonics).

Sheik-Bahae’s team has figured out how to cool a crystal down to 155 Kelvin (-180°F), which is more than 50 Kelvin colder than a solid has ever been cooled with a laser.  And it’s actually the coldest that any solid-state device has been able to get; thermoelectric cooling generally quits around 170 Kelvin.

What’s their secret?  Anti-Stokes fluorescence.  Most fluorescent materials demonstrate Stokes fluorescence, absorbing radiation at one wavelength and emitting radiation with a longer wavelength and less energy.  In anti-Stokes fluorescence, a material absorbs radiation and re-emits it at a shorter wavelength with higher energy, drawing the extra energy from the heat of the system.  If you keep exciting a material like this, its heat gets turned into light, and the material gets colder.  Then, once the material is frozen (assuming it is the door on a bank vault), you can crack through it with a hammer and make off with millions of dollars in canvas bags with money signs on them.

The problem, though, is that there aren’t too many materials that display anti-stokes fluorescence.  Ytterbium-doped yttrium lithium fluoride, the crystal used by Sheik-Bahae’s lab, is one of them.  That’s about it.  So it would be almost impossible to use laser cooling on anything practical, like a team of mystery-solving teenagers and their pesky mutt.  Unless, of course, the pesky mutt was made of ytterbium-doped yttrium lithium fluoride crystals.  But alas, I can only dream.

Sheik-Bahae can dream too: he believes that with more careful crystal preparation, purer laser light, and a little elbow grease, he can reach temperatures as low as 10K.  And I’d like to trust him.  After all, every step counts when you’re trying to develop a freeze ray.