NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance.

Support for this study was provided by the American Chemical Society; the American Institute of Chemical Engineers; the Defense Advanced Research Projects Agency under Contract No. MDA972-01-M-0001; the Camille and Henry Dreyfus Foundation, Inc. under Contract No. SG00-093; the National Institute of Standards and Technology under Contract No. NA1341-01-W-1070; the National Institutes of Health/National Cancer Institute under Contract No. N0-OD-4-2139; the National Science Foundation under Contract No. CTS-9908440; the U.S. Department of Energy/ Basic Energy Science under Contract No. DE-FG02-00ER15040; the U.S. Department of Energy/ Office of Industrial Technologies under Contract No. DE-AT01-01EE41424; and the U.S. Environmental Protection Agency under Contract No. CR828233-01-0.

All opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the organizations or agencies that provided support for this project.

Copyright 2002 by the National Academy of Sciences . All rights reserved.

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