Thomas: A little side article that gives us a more comprehensive look at where nanotechnology is starting to take us. What I would like to see, is a suit that keeps you warm in the winter - now that would be a smart material. Respectfully, Thomas Lunde -- > From: Mark Graffis <[EMAIL PROTECTED]> > > > Copyright © 1999 Christian Science Monitor Service > > By ALEX SALKEVER > > (August 8, 1999 12:12 a.m. EDT http://www.nandotimes.com) - When a > helicopter chatters loudly overhead in Boston, most people look up and > see the police or a traffic reporter. Harry Tuller sees ceramics. > > That's because the Massachusetts Institute of Technology scientist is > working on a revolutionary type of helicopter rotor that can > continuously change shape in midflight when zapped with electrical > charges. These rotors, made of a new class of materials called > electroceramics, could improve the performance and reliability of > helicopter flight. > > Tuller's electroceramics are just one of a myriad of so-called "smart > materials" that are increasingly emerging from labs and being used to > enhance performance safety, and efficiency in a wide range of > industries. > > Hybrid ceramic materials are embedded in snow skis to dampen > vibrations and smooth out the ride on the slopes. > > JCPenney stores are using super-thin display signs that look like > paper but contain words and numbers spelled out with thousands of > pigment-filled capsules made of a new type of electrically sensitive > plastic. These display signs, which can be reconfigured remotely, are > a likely precursor to portable newspapers that are constantly updated > with wireless data transmissions. > > Eyeglass frames made of "memory" metal alloys return to their original > shape when a certain temperature threshold is passed. > > These gee-whiz materials are merely the start of a new era in which > humanity will achieve stunning mastery over matter. > > "Only in the last decade, with the advent of more-powerful computers, > have we started to acquire the tools for trying to predict in advance > the relationship between a property and a structure," says Tuller. > > Knowledge is power > > Knowledge seekers have long coveted greater control over the materials > that make up the world. Medieval alchemists futilely attempted to > synthesize gold from lesser elements. And failure to understand the > nature of matter and the chemical elements has proven disastrous. In > the 19th century, physicians regularly prescribed heavy metals like > arsenic as remedies, which sometimes proved fatal. > > But when people have gained some mastery of crucial materials, they > have changed the course of history. Magnetic lodestones, for example, > allowed Chinese sailors to create navigational compasses, which led to > the first transoceanic explorations. > > But this pales in comparison to the threshold scientists stand upon > today. For the first time ever, researchers can examine complex > matrixes of molecules and predict how changing them will alter their > properties. > > This new and far deeper understanding of how matter acts and reacts > enables scientists to create materials that are not static but rather > reactive and malleable in relation to factors such as temperature, > electrical currents or physical stress. > > "A smart material can tell you something about a situation or a state > of affairs by responding in a predictable way to some kind of > stimulus," explains Art Ellis, a chemist at the University of > Wisconsin at Madison. > > Smart and intuitive > > Unlike past advances in material science, which have been far more > piecemeal, the current onslaught covers many fronts, from ceramics to > metals to plastics. And it is churning out discoveries at an > astonishing rate. > > Hand in hand with smart materials go recent advances in reducing the > size of microprocessors and computers. Scientists are now hard at work > integrating the two to create powerful systems that can be embedded in > everything from clothing to performance-enhancing spark plugs. > > But some smart materials are so intuitive that they actually will > eliminate the need for microprocessors that now generally control > things like air bags or other mechanical processes. > > The U.S. Navy has created a diving wet suit with tiny wax capsules > embedded in its material. The capsules melt at just below body > temperature, taking heat from the skin of a diver who is putting on > the dry suit and storing it. The heat is preserved in these capsules > and later shields the diver against cold water and keeps the suit > comfortable longer. > > The same method of regulating temperature is also used in boots. "When > we put our finger on a hot stove, we pull it back from the stove. A > really smart material system is like that. It is one in which there is > an automatic response in the right direction without a lot of > additional microprocessing power," says Tuller. > > Computer-as-laboratory > > Integral to this shift to smart materials has been rapid increases in > computing power. Real-world environments are often too impure or too > expensive for accurate laboratory experiments with these new > materials. > > Rather, scientists are finding it far easier to model materials on > computers first and then take their results to the bench. "Now the > models have gotten more sophisticated, the computers much more > powerful, and we are starting to see some really predictive > capabilities in some areas. More and more experiments will be done in > the computer rather than in the laboratory," says Tuller. > > As computer modeling has come into its own, scientists are also > applying these new techniques to study how to make traditional > materials smarter. > > "Even the low-tech materials we take for granted are chemically rather > complex and we still don't know how they behave," says Alistair > Cormack at Alfred University in New York. "We have been able to > analyze structures of glasses in a much more detailed way. Some people > are looking at the fracture process of glass at the atomic level." > > And the atomic level is precisely where the material science field > appears headed. Tunneling electron microscopes now allows scientists > to physically move individual molecules and even atoms. > > Three weeks ago scientists at UCLA and Hewlett-Packard announced they > had built "logic gates" on a molecular level into a crystal of > man-made material called rotaxane. These gates are the on-off > structures that describe the binary nature of bits of information and > are the most fundamental part of computer processors. This discovery > opened the realm for powerful computers far smaller than what the > human eye can see and far faster than anything known today. > > "We have this unprecedented control over matter on this nanoscale," > says Ellis. "The idea of being able to make materials in a controlled > way on this scale is just remarkable." > > (c) Copyright 1999. The Christian Science Publishing Society > > --------------------------- ONElist Sponsor ---------------------------- > > Show your ONElist SPIRIT! > http://www.onelist.com/store/tshirts.html > With a new ONElist SHIRT available through our website. > > ------------------------------------------------------------------------ >
