mm ommmm POLLUTION
MONSANTO, SOLUTiA SHELL OUT ON PCBS Firms to pay $600 million to settle claims by residents of Anniston, Ala. ONSANTO AND SOLUTIA I its chemicals business as Solutia will pay a combined $600 in 1997 Pharmacia & Upjohn million to settle claims of bought Monsanto in 2 0 0 0 and more than 20,000 residents of later spun it off as an agricultural Anniston, Ala., that their bodies products company and property were polluted with In Anniston, some of the nowpolychlorinated biphenyls. banned PCBs entered local waThe agreement, announced on terways, and tests show that Aug. 20, settles two PCB-relatsome local residents have d e ed cases, one in federal court with vated levels of the substances in about 17,000 plaintiffs and a sectheir bodies (C&EN, May 13, ond in state court with 3,500 2002, page 27). plaintiffs. The plant in Anniston Under the settlement, Monthat made PCBs between 1929 santo will provide approximately and 1971 was owned for decades $390 million in cash, commerby Monsanto. Monsanto spun off I cial insurance will cover about
M ANGRY Residents of Anniston, Ala., marched in protest on Aug. 19,2001.
NANOELECTRONICS
RAPID ASSEMBLY ORDERLY Randomly oriented silicon nanowires (background)can be organized into centimeter-sized patterns of crossed nanowire arrays (10 μιη Χ 10 μπι in the large inset).
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C&EN
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Method forms ordered, nanosized circuit elements on multiple length scales
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SOLUTION-BASED METHOD
for assembling nanowire structures from the bot tom up with spatial control on several length scales, ranging from nanometers to centimeters, has been demonstrated by scien tists at Harvard University Re
2003
searchers there have shown that large numbers of uniform and hi erarchically ordered nanoscale circuit elements can be prepared simultaneously using a simple and adaptable technique. Driven by potential benefits of ultra-high-density microelec tronics, researchers have devel oped and studied various test devices, such as field-effect tran sistors and light-emitting diodes, that are based on nanometerscale components. Although the studies have advanced the field toward the sophisticated logic and memory circuitry, in general, the tiny devices have been as sembled one at a time because of the limitations of available fabri cation methods.
$160 million, and Solutia will kick in $50 million over a decade. "The global settlement is in the best interest of Monsanto and our shareowners," compa ny President and C E O Hugh Grant comments. The settle ment removes a great risk— the uncertain length and outcome of litigation —to M o n s a n t o shareholders, he says. Solutia Chairman and CEO John C. Hunter III says, "We're glad to have this litigation behind us."The settlement puts the com pany in a better position to han dle its financial challenges, he says. In addition to the settlement dollars from Monsanto and So lutia, Pfizer, which purchased Pharmacia in April, will fund more than $75 million in envi r o n m e n t a l health care pro grams, including a clinic and re search facility, in Anniston. —CHERYLH0GUE
Now, Harvard chemistry pro fessor Charles M. Lieber and coworkers Dongmok Whang, Songjin, and Yue Wu have shown that numerous basic circuit com ponents can be constructed si multaneously using a straightfor ward procedure that controls the positions of nanowires or other building blocks and the devices constructed from them on mul tiple length scales [Nano Lett., published online Aug. 5, http:// dx.doi.org/10.1021/nl0345062]. In one demonstration, the Harvard group prepared ordered films of silicon nanowires using the Langmuir-Blodgett method, which provides control over the nanowire spacings on a length scale ranging from nanometers to micrometers. Then the team used layer-by-layer deposition meth ods and photolithography to con struct arrays of crossed nanowire junctions, which serve as func tional circuit components, form ing a regular pattern across an area of several square centimeters.— MITCH JAC0BY
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