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Welding with Laser-Beam Precision


Zeus hurled bolts of lightning at his enemies. And Flash Gordon zapped his foes with a laser. Back in the real world, a recently patented welding technology aims to merge these forces for more constructive uses. Developed by an Ohio State University team led by Charles Albright, a professor of industrial engineering, the Laser Assisted Arc Welder (LAAW) promises to marry the low cost of arc welding with the precision of laser joining.

Traditional arc welding has the advantage of being inexpensive, but it's tricky to control. As powerful electric arcs leap from welding rod to the metal, they sometimes follow unpredictable, lightning-like paths, leading to sloppy welds and splattered metal. Laser joining, on the other hand, is superprecise, but it requires a $200,000 device, along with a multikilowatt supply of electricity. So far, only deep-pocketed car and aerospace companies can afford such systems.

Albright's solution uses a low-power laser to guide the path of the electric arc. It's not a brand-new idea, but in the past such a technique has worked only with expensive, high-powered lasers. The LAAW is able to make do with a 7-watt laser source--about as powerful as a Christmas tree bulb--thanks to a secret ingredient: a wisp of carbon monoxide gas in the welding chamber. Tuned to just the right frequency, the laser can strip electrons from the carbon monoxide as it passes through--making an attractive path for the welding arc to follow. Albright and his team found that when the arc was brought near the laser, it followed along as if through a pipe, landing precisely where the laser was pointed.

With the LAAW freshly patented, Albright and his colleagues are looking for support to go commercial. Because LAAW uses such a miserly laser, it will be cheaper to buy and to operate than a conventional laser welding system. One day soon, Albright hopes, a $20,000 LAAW system, tethered to a $5,000 power supply, will be able to do the work of laser joiners that now cost 10 times more. Researchers, who have followed 593 families since 1975, report that the risk of certain mental illnesses triples in children whose parents are excessively harsh or abusive, or provide inadequate supervision.

In families with such poor parenting, 63% of the children developed depression, anxiety, drug abuse, or other psychiatric ailments by the time they were adults, says a report in the current Archives of General Psychiatry. The prevalence of such disorders in children in the general population is about 20%, said the study's lead author, Jeffrey G. Johnson, a psychologist at Columbia University and the New York State Psychiatric Institute. The families were drawn from all socioeconomic levels.

It has long been known that troubled parents are at increased risk of having troubled children. But researchers did not know exactly what role parenting played. The study found that the tripling of the risk occurred with poor parents with mental disorders and with poor parents without mental disorders. "That's the astonishing finding," says Johnson. "It didn't matter if the parents had disorders or not. It was the way they raised their children that determined whether the child had a disorder." The study was funded by the National Institute of Mental Health. The $419 billion chemicals industry in the U.S. is a research-driven affair. And yet its share of total U.S. research and development has been declining for years, from 11% in 1956 to about 8% in the past decade. Nobody knows why chemical spending is receding in the total R&D pie. But one reason may be that nobody has ever quantified exactly what kind of bang chemical companies get for their research buck.

Until now, that is. A new report from the Council for Chemical Research (CCR) analyzes data from more than 80 publicly traded chemical companies and concludes that on average, every dollar invested in chemical R&D today yields $2 in operating income over six years.

Members of the CCR suspected there was a substantial payback. "But until now, everything had been quite anecdotal," says Richard M. Gross, vice-president for research at Dow Chemical Co. and vice-chairman of the CCR. "We wanted to fill that void." In the next phase of the study, CCR plans to look at results from specific types of R&D and mine them for leads on which topics should be pursued most vigorously. -- That grit in your eyes last month may have come from China. NASA scientists using satellite instruments monitored what they are calling the largest dust storm in the northern hemisphere since 1979. The cloud kicked up in Northern China in April, then wafted over North Korea and Japan, ultimately raining dust over large swaths of North America before dissipating in the mid-Atlantic. See http://science.nasa.gov/headlines/y2001/ast22may_1.htm for maps and images.

-- EPRIsolutions, a subsidiary of the Electric Power Research Institute, will soon be installing fuel cells in a handful of Chicago residences to test the technology's economic and environmental benefits. The furnace-size cells, which convert natural gas directly to electricity, produce 3 to 7 kilowatts of electricity and could be commercially viable in about two years, according to EPRI.


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