Developments to Watch
NANOTUBES TO LIGHT UP GLASS DISPLAYS
SINCE THEIR DISCOVERY IN 1991, slender molecules known as carbon nanotubes have entranced scientists. The tubes, an elongated form of carbon-60 molecules known as buckyballs, are extremely tough and can function either as conductors or as semiconductors. But growing the tubes in a form suited to electronics applications has proven extremely difficult.
Not anymore. Zhifeng Ren, a research associate professor of physics and chemistry at the University of Buffalo, has developed a process for growing usable nanotubes--each just a few billionths of a meter in diameter--at relatively low temperatures. Like other scientists, Ren uses lasers to evaporate chemicals and form a carbon residue. He broke new ground, however, when he combined acetylene and ammonia gases in a chemical-vapor deposition technique. Within a few minutes, his method can produce hundreds of millions of nanotubes, growing in neat rows, perpendicular to the surface of a glass panel.
Ren says the first application might be a new type of flat-panel display. The nanotubes could precisely deliver electrons to phosphor dots on a glass plate, causing them to glow and create a picture. Scientists at Sandia National Laboratories are helping Ren test his tubes and find potential commercial partners.EDITED BY OTIS PORTReturn to top
HOW TO TALLY PRODUCTIVITY ON THE SHOP FLOOR
BECAUSE MOST TOP MANAGERS WERE WEANED on finance or marketing, manufacturing often gets short shrift when capital budgets are drawn up. Consultants find that manufacturers routinely funnel millions into reducing costs, yet pinch pennies when it comes to the factory, where investment can bring big gains in productivity and profits.
Bernard D. Asher, president of Real World Technology Corp. in Mt. Prospect, Ill., hopes to change all that. He has come up with a management tool, dubbed the manufacturing productivity index (MPI), that's simple but revealing: MPI is the product of throughput efficiency times gross margin percentage times revenue. The raw data are readily available, so the result could be a clearer understanding of the payback potential of factory investments.
Asher has selfish reasons for trying to spur factory investments. His company sells a $150,000 software package, called OnTrak, for scheduling shop-floor operations. But his MPI idea has struck a chord. Ernst & Young may adopt it in its consulting practice. And Boston consultant AMR Research Inc. advised its clients that MPI "is a step in the right direction," then promptly fielded a dozen calls from interested companies.EDITED BY OTIS PORTReturn to top
SUGAR-COATED CELLS THAT MAKE INSULIN
TO ELIMINATE THE NEED FOR INSULIN INJECTIONS, medical researchers have tried repeatedly to transplant insulin-producing cells, called "islets of Langerhans," into diabetics. But the cells are quickly tagged as foreign and rejected by the patients' immune systems.
Now, researchers at Duke University have devised a new approach that promises to shield the islet cells from attack. The scientists use a special netlike microcapsule to surround insulin-producing cells, then they implant the capsule. The holes in the net are small enough to prevent immune-system T-cells from squeezing through. But they're large enough to let nourishing oxygen molecules in--and to allow insulin to flow freely out. In tests with diabetic rats, the method reduced blood-sugar levels by 25% for more than a week.
Interestingly, sugar is the key to the new capsules. They're made from liquid polymers, or hydrogels, that contain sugar molecules engineered to react to light. So, when coated cells are hit by a laser, the liquid solidifies, and the sugar molecules link up to form the backbone of the mesh structure. Despite positive results, chemist Mark W. Grinstaff, who heads the project, says it will take more than five years of further animal testing before human trials can begin. Meanwhile, his team is experimenting with different kinds of polymers that might be used to deliver toxic medicines.EDITED BY OTIS PORTReturn to top