NANOCATALYST BEHAVIOR OBSERVED

Catalysts made of small particles of metals such as platinum are
widely used in the chemical and refining industries, as well as in
catalytic converters in automobile tailpipes. Now researchers at the
University of California, Davis, studying irridium catalysts just
four atoms in size have found some unexpected behavior that could
open the way for a new class of nano-sized catalysts.

By directly observing the steps in chemical reactions, the
researchers found that modifying the support material under
catalytic nanoparticles had a dramatic effect, said UC Davis
chemical engineer Bruce Gates, who led the research team.
Previously, the support material was thought of as little more than
something to hold the catalyst in place, Gates said. The results are
published in the Feb. 7 issue of Nature.

Gates, with graduate students Andrew Argo, Felix Lai and
undergraduate Josip Odzak, made nanoclusters of four irridium atoms
each -- one atom sitting on three in a tiny pyramid -- on different
support materials. Significantly, they were able to make their
catalysts nearly uniform. They used the irridium nanoclusters to
react propene and hydrogen to form propane gas.

To their surprise, they found that changing the support material
changed the efficiency of the catalyst up to ten-fold. They also
found that the catalytic nanoclusters and the support were
chemically bonded to each other, so that the support had a marked
effect on the catalyst.

Understanding how solid catalysts work has been a difficult
challenge for chemists, Gates said. By using the new theory and
experimenting with different arrangements of nanocluster catalysts
and support materials, scientists and engineers would be able to
design new catalysts for specific functions, Gates said.

Media contacts: Bruce Gates, Chemical Engineering and Materials
Science, (530) 752-3953, bcgates@ucdavis.edu; Andy Fell, News
Service, (530) 752-4533, ahfell@ucdavis.edu

NANOMATERIALS EXPERT
WINS FRANKLIN MEDAL IN EARTH SCIENCES

Alexandra Navrotsky, director of the cross-disciplinary nanoscience
initiative at the University of California, Davis, has been awarded
a prestigious Benjamin Franklin Medal in Earth Sciences for her work
on the thermochemistry of minerals, high pressure materials, and
nanomaterials. Described as "the American Nobels," this year's
Franklin medals will be presented April 25 in a ceremony at the
Benjamin Franklin National Memorial in Philadelphia.

Navrotsky's studies of how materials form different structures under
intense heat and pressure has shown how minerals behave deep within
the earth's core and on other planets.


Her laboratory is particularly interested in nanomaterials, which
are made up of very small particles just a few atoms across. Because
of their small size, nanomaterials have unusual chemical, electrical
and other properties and interact readily with living things.


Many processes in geology occur at the nanoscale, Navrotsky said.
She has been a co-principal investigator in the Center for High
Pressure Research, a Science and Technology Center established by
the National Science Foundation to study the deep interior of the
Earth and other planets.


At UC Davis, Navrotsky holds the Edward Roessler Chair in
Mathematical and Physical Sciences and leads the UC Davis initiative
on Nanophases in the Environment, Agriculture and Technology (NEAT),
which supports interdisciplinary research, education and training
related to nanoscience and nanomaterials.


Franklin Medals are awarded every year in the categories of earth
science; chemistry; computer and cognitive science; engineering;
life science and physics. Ninety-eight Franklin laureates have gone
on to win Nobel prizes, including Marie Curie, Albert Einstein and
Stanley Prusiner. Other past Franklin laureates include Orville
Wright, Noam Chomsky, Thomas Edison and Stephen Hawking.


More information:
-- http://www.fi.edu/tfi/exhibits/bower/index.html
-- http://navrotsky.engr.ucdavis.edu/
-- http://neat.ucdavis.edu/


Editor's note: A photo of Alexandra Navrotsky is available. Contact
Andy Fell for details.


Media contacts: Alexandra Navrotsky, Thermochemistry Facility, (530)
752-9289, anavrotsky@ucdavis.edu; Evan Welsh, Franklin Institute,
(215) 448-1176, ewelsh@fi.edu; Andy Fell, UC Davis News Service,
(530) 752-4533, ahfell@ucdavis.edu



MEDIA SOURCE:
NANOPARTICLES, AIR POLLUTION, CLIMATE AND HEALTH


Anthony Wexler, an atmospheric scientist at the University of
California, Davis, studies how very small particles -- measured in
nanometers, or billionths of a meter -- contribute to air pollution
and affect human health and climate. The role of these atmospheric
nanoparticles, which can come from both man-made and natural
sources, is one of the largest unknowns in understanding global
climate change, Wexler said. Clouds form when water droplets form
around nanoparticles, and the thickness and whiteness of clouds
affects how much heat from the sun is reflected back into space.
Wexler has developed new equipment for analyzing single
nanoparticles in polluted air. He is participating in an
Environmental Protection Agency project to monitor air quality in
selected cities including Pittsburgh, Pa., Houston, Tx., and Fresno,
Calif. He also studies how particles of different sizes are carried
through the airways into the lungs, and how they can affect human
health. Contact: Anthony Wexler, Mechanical and Aeronautical
Engineering, (530) 754-6558, aswexler@ucdavis.edu.



MEDIA SOURCE: NANOPARTICLES, COMBUSTION AND AIR POLLUTION


Ian Kennedy, a professor of mechanical engineering at the University
of California, Davis, studies how very small particles of metal and
carbon (soot) -- measured in nanometers, or billionths of a meter --
are formed within flames. These nanoparticles can come from burning
oil and coal, from diesel engines and from processes such as
welding. They contribute to air pollution and because of their small
size, may play an important role in human health. Kennedy has
developed methods that use lasers to study how nanoparticles are
formed by flames and how they move. He also collaborates with
researchers at the UC Davis School of Veterinary Medicine to study
the health effects of nanoparticles created by combustion. Contact:
Ian Kennedy, Mechanical and Aeronautical Engineering, (530) 752-
2796, imkennedy@ucdavis.edu.
NANOCATALYST BEHAVIOR OBSERVED


Catalysts made of small particles of metals such as platinum are
widely used in the chemical and refining industries, as well as in
catalytic converters in automobile tailpipes. Now researchers at the
University of California, Davis, studying irridium catalysts just
four atoms in size have found some unexpected behavior that could
open the way for a new class of nano-sized catalysts.


By directly observing the steps in chemical reactions, the
researchers found that modifying the support material under
catalytic nanoparticles had a dramatic effect, said UC Davis
chemical engineer Bruce Gates, who led the research team.
Previously, the support material was thought of as little more than
something to hold the catalyst in place, Gates said. The results are
published in the Feb. 7 issue of Nature.


Gates, with graduate students Andrew Argo, Felix Lai and
undergraduate Josip Odzak, made nanoclusters of four irridium atoms
each -- one atom sitting on three in a tiny pyramid -- on different
support materials. Significantly, they were able to make their
catalysts nearly uniform. They used the irridium nanoclusters to
react propene and hydrogen to form propane gas.


To their surprise, they found that changing the support material
changed the efficiency of the catalyst up to ten-fold. They also
found that the catalytic nanoclusters and the support were
chemically bonded to each other, so that the support had a marked
effect on the catalyst.


Understanding how solid catalysts work has been a difficult
challenge for chemists, Gates said. By using the new theory and
experimenting with different arrangements of nanocluster catalysts
and support materials, scientists and engineers would be able to
design new catalysts for specific functions, Gates said.


Media contacts: Bruce Gates, Chemical Engineering and Materials
Science, (530) 752-3953, bcgates@ucdavis.edu; Andy Fell, News
Service, (530) 752-4533, ahfell@ucdavis.edu



NANOMATERIALS EXPERT
WINS FRANKLIN MEDAL IN EARTH SCIENCES


Alexandra Navrotsky, director of the cross-disciplinary nanoscience
initiative at the University of California, Davis, has been awarded
a prestigious Benjamin Franklin Medal in Earth Sciences for her work
on the thermochemistry of minerals, high pressure materials, and
nanomaterials. Described as "the American Nobels," this year's
Franklin medals will be presented April 25 in a ceremony at the
Benjamin Franklin National Memorial in Philadelphia.


Navrotsky's studies of how materials form different structures under
intense heat and pressure has shown how minerals behave deep within
the earth's core and on other planets.


Her laboratory is particularly interested in nanomaterials, which
are made up of very small particles just a few atoms across. Because
of their small size, nanomaterials have unusual chemical, electrical
and other properties and interact readily with living things.


Many processes in geology occur at the nanoscale, Navrotsky said.
She has been a co-principal investigator in the Center for High
Pressure Research, a Science and Technology Center established by
the National Science Foundation to study the deep interior of the
Earth and other planets.


At UC Davis, Navrotsky holds the Edward Roessler Chair in
Mathematical and Physical Sciences and leads the UC Davis initiative
on Nanophases in the Environment, Agriculture and Technology (NEAT),
which supports interdisciplinary research, education and training
related to nanoscience and nanomaterials.


Franklin Medals are awarded every year in the categories of earth
science; chemistry; computer and cognitive science; engineering;
life science and physics. Ninety-eight Franklin laureates have gone
on to win Nobel prizes, including Marie Curie, Albert Einstein and
Stanley Prusiner. Other past Franklin laureates include Orville
Wright, Noam Chomsky, Thomas Edison and Stephen Hawking.


More information:
-- http://www.fi.edu/tfi/exhibits/bower/index.html
-- http://navrotsky.engr.ucdavis.edu/
-- http://neat.ucdavis.edu/


Editor's note: A photo of Alexandra Navrotsky is available. Contact
Andy Fell for details.


Media contacts: Alexandra Navrotsky, Thermochemistry Facility, (530)
752-9289, anavrotsky@ucdavis.edu; Evan Welsh, Franklin Institute,
(215) 448-1176, ewelsh@fi.edu; Andy Fell, UC Davis News Service,
(530) 752-4533, ahfell@ucdavis.edu



MEDIA SOURCE:
NANOPARTICLES, AIR POLLUTION, CLIMATE AND HEALTH


Anthony Wexler, an atmospheric scientist at the University of
California, Davis, studies how very small particles -- measured in
nanometers, or billionths of a meter -- contribute to air pollution
and affect human health and climate. The role of these atmospheric
nanoparticles, which can come from both man-made and natural
sources, is one of the largest unknowns in understanding global
climate change, Wexler said. Clouds form when water droplets form
around nanoparticles, and the thickness and whiteness of clouds
affects how much heat from the sun is reflected back into space.
Wexler has developed new equipment for analyzing single
nanoparticles in polluted air. He is participating in an
Environmental Protection Agency project to monitor air quality in
selected cities including Pittsburgh, Pa., Houston, Tx., and Fresno,
Calif. He also studies how particles of different sizes are carried
through the airways into the lungs, and how they can affect human
health. Contact: Anthony Wexler, Mechanical and Aeronautical
Engineering, (530) 754-6558, aswexler@ucdavis.edu.



MEDIA SOURCE: NANOPARTICLES, COMBUSTION AND AIR POLLUTION


Ian Kennedy, a professor of mechanical engineering at the University
of California, Davis, studies how very small particles of metal and
carbon (soot) -- measured in nanometers, or billionths of a meter --
are formed within flames. These nanoparticles can come from burning
oil and coal, from diesel engines and from processes such as
welding. They contribute to air pollution and because of their small
size, may play an important role in human health. Kennedy has
developed methods that use lasers to study how nanoparticles are
formed by flames and how they move. He also collaborates with
researchers at the UC Davis School of Veterinary Medicine to study
the health effects of nanoparticles created by combustion. Contact:
Ian Kennedy, Mechanical and Aeronautical Engineering, (530) 752-
2796, imkennedy@ucdavis.edu.