The Cutting Edge: COMPUTING / TECHNOLOGY / INNOVATION : Calling the Ultrasonic Haz-Mat Squad
Michael Hoffmann, professor of environmental chemistry at the California Institute of Technology, thinks that one way to neutralize toxic chemicals in water is to blast them with sound.
When sufficiently powerful ultrasound is sent through a liquid, microscopic bubbles form, swelling until they reach a size whose natural resonant frequency--the wavelength of its vibrations--equals the ultrasound frequency. Like wine glasses shattered by powerful soprano voices, the bubbles absorb sound energy, balloon outward and collapse, all in a few microseconds.
As they explode, the temperature inside the bubbles briefly soars as high as 5,500 degrees Celsius. That’s hot enough to incinerate any organic chemical. Hoffman’s group has worked with drug, heavy manufacturing and electronics firms, all of which produce chemicals that are difficult and costly to treat.
Thanks for the Memory: Unless you are one of those who believe you can’t be too thin, too rich or have too much computer memory, Christmas morning could turn out to be memorable in all the wrong ways.
Multimedia-equipped home computers are expected to fly off the shelves this holiday season. But many of the systems being sold might not support the most popular software programs, some of which are serious memory hogs.
The mega-hit “Doom,” for example, devours 15 megabytes of hard disk space, and another must-have game, “Strike Commander,” logs in at 11 MB. And if you purchase a high-capacity hard disk, there is the computer’s internal memory to consider.
Just in time for the holidays comes Stac Electronics with its Multimedia Stacker. The program uses the same compression technology in Stac’s original products to squeeze more than twice as much space out of the hard drive.
Multimedia Cloaking, which was developed by Helix Software, is included free with the Stac multimedia product to deal with the internal memory problems.
Because all of the multimedia add-ons such as sound cards and video boards take up a good chunk of the 640K of “lower memory” DOS allots for running programs, a multimedia program that needs 600K of that lower memory won’t run. Essentially, Multimedia Cloaking puts enough of the drivers for the multimedia peripherals into extended memory, freeing up the lower memory for the games. Multimedia Stacker sells for less than $100 retail.
Eat Your Explosives: No one should horse around with explosives. But that’s what Kimberly Ogden, an assistant professor of chemical engineering at the University of Arizona, and researchers at Los Alamos National Laboratory in New Mexico are doing--sort of. They’re using bacteria commonly found in horse manure to eliminate the explosive residues left over from the manufacture of RDX, the military equivalent of TNT.
The bacteria eat the carbon and nitrates that are the active ingredients in RDX, converting them to carbon dioxide and other more stable compounds.
Because TNT and RDX must be kept wet during their manufacture--a single spark could set them off--a great deal of dangerous waste water is left over.
Normally, explosives makers use charcoal filters to clean the water, then toss the contaminated charcoal. Or they let the water evaporate and burn the residue. But if bacteria are allowed to convert the explosives that accumulate in the filters, the charcoal can be used to filter more water.
Gluing Chips With Static Cling: Electrostatic charges are no fun when you get zapped by a door handle or find your new skirt glued to your legs. But at the Commerce Department’s National Institute of Standards and Technology, these same charges are being put to good use. Researchers in NIST’s Materials Science and Engineering Laboratory have patented a process that makes the charges act like a glue to stick the smooth surfaces of silicon oxide and some forms of gallium arsenide together.
The naturally acidic surfaces of these materials readily give up positively charged subatomic particles, or protons. By bonding a single molecular layer of a basic chemical that wants to take on extra protons to the silicon oxide, a proton exchange occurs. When the silicon oxide and the gallium arsenide come together, the two surfaces are oppositely charged--and the electrostatic pull “glues” them together. Like sticky Post-it notes, the top layer can be peeled off and repositioned.
There are no commercial applications at the moment, but the electrostatic glue could prove useful in creating hybrid chips, especially because the glue layer is very thin.
