Title: Scientists Discover New, Self-Repairing Plastic
Date:  March 4, 2002
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tips, please contact the public information officer at the end of
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      SCIENTISTS DISCOVER NEW, SELF-REPAIRING PLASTIC
    A team of chemists and engineers has developed a strong,
transparent plastic that can mend itself if fractured.  The
discovery is expected to lead to the creation of self-repairing
products for industrial, military and scientific applications.
Fractures in the new polymer, called Automend, can be healed
without adding catalysts or other chemicals by heating the
material to 240-250 degrees Fahrenheit (about 120 degrees
Celsius).  The National Science Foundation (NSF)-funded
scientific team was led by Fred Wudl, director of the Exotic
Materials Institute at the University of California, Los Angeles
(UCLA), and reported its findings in the Mar. 1 issue of Science.
     The material was created while Wudl's team was attempting to
produce a material as hard as diamond.  The scientists obtained
additional funds to branch off into this separate but related
area of research.  The special provision is reserved for rare
occasions when an accomplished scientist is given the opportunity
to extend his or her primary research goals to pursue an equally
promising objective.
     According to Wudl, the self-healing plastic is potentially
useful for products such as electronic devices that heat and cool
frequently and large lenses that would retain their shape if
cracked and repaired.  Because the material is transparent to
electromagnetic waves, it could be used to house radar or
communications equipment.  [Amber Jones]
      NEW MATERIALS KEY TO SHRINKING MEMORY DEVICES
     Scientists at the University of Minnesota recently announced
a new milestone in the miniaturization of logic and memory
components for computers and other electronic devices.
    As devices shrink, so too must the thin films of silicon
oxide at the heart of the machines.  However, at some point the
insulating properties of silicon oxide films diminish.
     Chemist Wayne L. Gladfelter and his colleagues, with support
from NSF, have perfected a method to optimize the physical
properties of high-dielectric materials.  These electrically
insulating materials are being considered as replacements for
silicon oxide.
     Gladfelter s team has developed a chemical vapor method of
depositing three metal oxides on a single wafer in various
combinations to achieve size and performance objectives.  The
researchers reported their results in the February 2002 issue of
Chemistry of Materials.  [Amber Jones]
 RESEARCHER CATALOGS VAST DATABASE OF TRADITIONAL
                 PLANTS USED BY NATIVE AMERICANS
     A scholar at the University of Michigan-Dearborn has
compiled information on plants used by Native Americans for
foods, drugs, dyes and fibers -- more than 47,000 uses for nearly
4,000 species of plants.
     Through an NSF grant of $256,000, anthropology professor
Daniel E. Moerman analyzed the relationship of the 4,000 species
with the entire collection of plant species in North America
(about 28,000) and also their relationship to plant species with
medicinal value (about 2,800).
     Pharmacologists are uncovering medical applications, such as
the uses of cattail for treating burns, while native groups are
using the data to reconstruct habitats and build native medicinal
herb gardens.  A school district in the Four Corners region of
the U.S. is also using the database to put together a bilingual
(English and Navajo) website that shows how local native people
used plants. [Bill Harms]
For more information, see:
http://www.umd.umichgian.edu/cgi-bin/herb
                   ALGORITHMS FOR AIRLINES:
           NEW MATH MODEL SAVES TIME, MONEY
    To plan flight schedules, airlines must match capacities
with demands, and weigh the costs of non-stops flights and
through connections against the prices passengers are willing
to pay.  In research partially funded by NSF, a team of
operations researchers and industrial engineers developed a
mathematical model that efficiently identifies the most
profitable assignment of planes to flight legs and  through
connections.
     The research team, led by James Orlin of the Massachusetts
Institute of Technology and Ravindra Ahuja of the University of
Florida, also developed the software for the model.
     United Airlines is adopting the mathematical model to
improve the efficiency of flight scheduling and allow planning
decisions within seconds.
     Previously, an airline's ability to assign flights in an
integrated manner was impractical because of the large amounts of
computer time needed.  Using the more efficient software and
mathematical model, the researchers estimate, could save the
airline as much as $25 million annually.
   The researchers are now expanding the model to include
additional criteria such as crew costs, reliability, and flexible
flight departure times. [Amber Jones]
                              -NSF-