1% increase in earnings to $52.9 million while sales improved 7% to $654 million. However, much of the earnings improvement came from a lower effective tax rate. Two companies reported healthy earnings increases. At Great Lakes Chemical, earnings rose almost 13% to $38.7 million on a 27% sales in-
crease to $319 million. And at Imcera, earnings from continuing operations were up 54% to $27.2 million. Sales rose 10% to $409 million. Imcera chairman George D. Kennedy said, "New products, capacity additions, and improved operating performance all contributed." William Storck
Plan to stem Great Lakes pollution unveiled On April 12, Environmental Protection Agency Administrator William K. Reilly and governors or representatives of the eight Great Lakes states announced a comprehensive plan for voluntary action to stop the generation of pollution in the Great Lakes region. In introducing the program at a meeting in Chicago, Reilly said EPA regards this as a unique opportunity to build environmental protection into the region's industries and infrastructure as these undergo rapid modernization. In the past, most environmental regulations have concerned cleaning up or removing pollution from a factory's output or from waste disposal sites. "Pollution prevention" aims to change manufacturing processes and life-styles so that they generate less pollution. The EPA plan consists of four major projects: helping the Big Three automakers and related industries develop manufacturing processes that produce smaller amounts of toxic substances; developing a program to stop degradation in Lake Superior where the water is still relatively pristine; beginning pilot programs in Rochester and Buffalo, N.Y., to prevent water pollution from diffuse nonindustrial sources, such as household hazardous waste and lawn care products; and holding an international symposium in September 1991 to assess progress and plan future strategies. Although most environmental groups regard the action plan as an important first step, some of them predict that it will not be very effective. "We think it is very positive that EPA and the Great Lakes governors have taken pollution prevention initiatives," says Philip Weller, executive director of Great Lakes
United, a U.S.-Canadian coalition of interest groups. However, he is concerned that the program is voluntary and says it lacks detail. "There has to be a rigorous across-the-board reduction program." "Voluntary reduction of a few pollutants is only a starting place," says Carolyn Raffensperger, staff director for the Illinois chapter of the Sierra Club. Jack Weinberg, coordinator for Greenpeace's Great Lakes project expresses similar views. G o r d o n D u r n i l , t h e U.S. cochairman of the International Joint Commission, is more optimistic. "As long as the governments are saying the words and agreeing that this ought to be done, you're on your way to getting it done," he says. The IJC is a binational body that assesses what governments are doing to meet their commitments in the Great Lakes Water Quality Agreement of 1972 (amended in 1987), under which the U.S. and Canada have committed to virtually eliminate toxic substances in the Great Lakes. "I think you'll find that Canada will be joining in [the program] soon," he predicts. Bette Hileman
FROMATIANTA
DNA code sequenced for spider silk proteins Molecular biologists at the University of Wyoming have sequenced the DNA coding for the protein structures that give one form of spider silk its combination of incredible strength and elasticity. If the silk were available in commercial q u a n t i t i e s a n d at low enough cost, it could have signifi-
cant applications. In the medical field, for example, it might find use in artificial tendons or sutures, since it isn't rejected by the body. It could be used as reinforcing fibers for composites, or if the cost were low enough, in fabrics. At this stage of development, such uses are most likely a good way off. But "there are no theoretical barriers that we can see," says Wyoming professor of molecular biology Randolph V. Lewis. Cloning of the silk, made possible by the DNA sequencing, could lead to an economical way to mass produce it. The silk in question is dragline silk, one of six forms with different properties made, in the Wyoming work, by the spider Nephila clavipes, a thumb-sized tropical species also known as the golden orb web spider. Dragline silk forms the outer edge of a web. It is five times stronger than steel and 10 times stronger than silkworm silk, putting it in the region of aramid fibers. Its elasticity is twice that of nylon. Research in the field has suggested spider silk is composed of a large protein. The protein forms fibers that consist primarily of crystalline regions interspersed with amorphous regions. Since there are no changes in the amorphous regions when the silk is stretched, Lewis says, it has been suspected that the amorphous regions contribute substantially to the elastic properties of the fiber. Stretching the fiber, he says, induces the formation of a helical structure in the amorphous regions, but when tension is released that structure returns to the more stable amorphous state. Cloning the DNA for the major protein in dragline silk, Lewis and his group found the protein has a repeating sequence of 34 amino acids, which appears to have three segments. In further work, the group found that a second protein was present. There are similarities to the first protein, Lewis says, but with major differences in the crystalline regions, where there are different amino acid components. The second protein appears to comprise less than 10% of the silk fiber. Lewis speculates on what prov i d e s t h e fiber w i t h its great strength. The second protein, he April 22, 1991 C&EN
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News of the Week says, can only loop across the fiber rather than along its length, and it forces the first protein to assume the same structure. The loops flex, and for the fiber to break, each protein molecule across it must be broken. To study the properties of the proteins, the Wyoming group has begun expressing them in genetically engineered bacteria. However, the bacteria do not produce adequate working levels of the silk. Lewis explains that since there are large amounts of only a couple of amino acids used, a metabolic burden is probably put on the bacteria, which simply do not tolerate the foreign DNA and just throw it out. One admittedly futuristic approach now being considered by Lewis' group is to use an insect virus and infect silkworms to make the spider silk. The group is also now looking at yeasts, since yeasts are generally more tolerant of foreign DNA than bacteria. Some companies, Lewis notes, have suggested the group consider plants—for example, genetically engineering cotton plants—to do the job. James Krieger
Japan expected to help fund supercollider A logjam has apparently been broken over Japanese support for construction of the Department of Energy's controversial $8.2 billion Superconducting Super Collider. The Japanese had been reluctant to commit themselves to support the megaproject. But the issue was on the agenda when President Bush and Japanese Prime Minister Toshiki Kaifu met earlier this month. Administration sources are not speaking for the record. But partly as a result of Japan's wish to smooth some of the bad feeling in the U.S. over its lack of participation in the Persian Gulf War, it has decided to help with SSC construction. The hangup in Japan stemmed from several considerations. First, the amount the U.S. was asking— about $1 billion—was too much for any single science agency to fund. The Japanese also wanted assurance the project would not suffer the on12
April 22, 1991 C&EN
again off-again politics the space station Freedom has undergone. And they wanted a say in the planning. The deal worked out is this. Japan definitely will commit $1 billion in support if Congress approves the full $534 million the Administration is asking for the project for fiscal 1992. The Japanese also expect involvement by private contractors. "You'd be surprised at the unity n o w , " says one Administration source. "The big hurdle is what Congress does. If Congress approves the full amount, we'll put the full court press on them and they will come through with the $1 billion." The source also says Japanese commitment should release similar support from Europe. The state of Texas has already promised $1 billion. Everyone involved in the project— including the Japanese—knows Congress is unlikely to appropriate the full $534 million. But it is said the
Japanese would maintain their commitment for anything over a $300 million appropriation. "That'll be easy," says a House source. The House Budget Committee has already approved a $320 million increase in DOE's general science budget—$80 million below the Administration's request—and that should cover the minimum required by the Japanese. Anything less, however, would cancel the commitment, and $200 million would "put the whole project at risk," says the Administration source. Meanwhile, in Waxahachie, Tex., site of the SSC, more than 1000 persons already have been hired and contracts are being let for development of particle detectors, cables, cryogenic systems, and magnets. Actual construction will begin once Congress completes its appropriations process. Wil Lepkozvski
Single-crystal diamond films made on copper A technique has been developed that could expedite microelectronics applications of diamond thin films. The method uses a pulsed laser to change carbon atoms into diamond on inexpensive copper substrates. It was developed by Jagdish Narayan and Vijay P. Godbole of North Carolina State University (NCSU) and C. Woody White of Oak Ridge National Laboratory [Science, 252, 416 (1991)]. Diamond thin films are the subject of intensive research worldwide. Their high charge-carrier mobility, low dielectric constant, high breakdown strength, high thermal conductivity, and other properties make them potentially valuable for use in high-speed computers, high-temperature electronics applications (such as in auto and aircraft engines), and communications equipment. Up to now, single-crystal diamond thin films suitable for such applications have been grown only on expensive diamond substrates. Although diamond thin films have been formed on nondiamond substrates such as silicon and various metals, such films are polycrystalline (consisting of multiple crystals) and contain dislocations, grain
boundaries, and other defects that make them unsuitable for electronics use. The films developed by Narayan and coworkers, however, are defect-free single crystals up to several square micrometers in area. Materials scientist Russell Messier of Pennsylvania State University says the new technique "has the potential for being important." He notes that increasing the size of the diamond single crystals to areas on the order of square centimeters is "a reasonable goal to shoot for" if they are to be of practical use in commercial devices. However, Narayan says there is no fundamental limitation to scaling the process up to produce larger area films. And he says he has already produced films of square-centimeter size in the laboratory. The new method involves epitaxial carbon-ion implantation on copper, followed by pulsed laser irradiation to melt and rapidly solidify (laser-anneal) the surface. The researchers believe this process causes the implanted carbon atoms to cluster, forming the crystalline phase. NCSU has applied for a patent on the process. Stu Borman
