#98-81

Mailed 8/27/98

 

BNL SPOTLIGHTS

 

NOTE TO EDITORS: "BNL Spotlights" is issued periodically to bring you up to date on some of the latest newsworthy developments at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory. For more information on any of these items, call Diane Greenberg or Mona S. Rowe at BNL's Public Affairs Office at (516)344-2345.

 

NEW MICROSCOPE OFFERS UNPRECEDENTED IMAGES OF ATOMS

Brookhaven Lab's new, one-of-a-kind, 300-kilovolt microscope can image single atoms in materials as varied as high-temperature superconductors and human tumor cells. Built by JEOL of Tokyo, this $2 million high-resolution transmission electron microscope can be used to magnify samples up to 50 million times. Brookhaven scientists plan to use the microscope to determine the atomic structure of materials, which will help them to understand their characteristics. In addition, a material's chemical composition can be examined with the microscope at atomic-scale resolution.

In a recent experiment, Brookhaven researchers looked at a high-temperature superconductor, yttrium barium copper oxide, and were able to determine its local electronic structure, its arrangement of atoms, bonding, and interactions among the atoms. In the future, Brookhaven researchers plan to use the microscope to study the distribution of boron in brain tumor cells. Boron is administered along with radiation to patients in a promising experimental brain tumor therapy called boron neutron capture therapy. Clinical trials of this therapy are now under way at Brookhaven Lab. Such investigations may lead to more efficient superconductors and boron compounds that more effectively kill tumors on contact.

 

UNDERSTANDING OZONE POLLUTION

City smog breeds excess ozone, and, thus, most major metropolitan areas in the U.S. do not meet national ambient air-quality standards. Too much surface ozone can cause or aggravate respiratory problems in humans and damage crops and other vegetation.

Brookhaven Lab scientists are currently focusing on Phoenix, Arizona, where ozone levels are high, to understand the chemical precursors in the region that lead to ozone formation, to measure the ozone concentration in the air, and to determine what chemicals are created along with ozone. Brookhaven's collaborators on this project - Argonne National Laboratory, Pacific Northwest National Laboratory, and the Arizona Department of Environmental Quality - are studying meteorological conditions in Pheonix and correlating them to ozone dispersal in the region. Previously, Brookhaven and its collaborators have studied ozone formation in New York City and Nashville, Tennessee. This research may lead to a better understanding of how ozone levels can be reduced.

 

CHEMISTS ACHIEVE 'ARTIFICIAL PHOTOSYNTHESIS'

Burning fossil fuels creates excess carbon dioxide in the Earth's atmosphere and may lead to global warming. Scientists at Brookhaven Lab have been performing basic research that may help to overcome this cycle of pollution by converting carbon dioxide into useful chemicals and nonpolluting fuels, such as methanol. The researchers use catalysts to promote the reaction of carbon dioxide with other substances.

Recently, chemists from Brookhaven, the National Institute of Standards and Technology and Howard University sought inspiration from nature. They chose a class of catalysts derived from iron and cobalt porphyrins, similar in structure to the chlorophyll molecule that helps plants perform photosynthesis, the process in which they convert carbon dioxide and water to cellulose and oxygen in the presence of sunlight. These artificial porphyrins change light energy into chemical energy by converting carbon dioxide to formic acid and carbon dioxide, which can then serve as chemical feedstocks for other processes. The basic understanding derived from the study may aid in the design of useful chemicals and fuels.

 

A NEW LOOK AT LIVING CELLS

How do cells grow? How do they die? Scientists have had limited knowledge of the biological processes that are common to all cells. Now researchers from Brookhaven Lab and the University of Paris have, for the first time, obtained images of proteins, lipids and nucleic acids inside intact, living mouse cells. In particular, they saw the movement and location of lipids, or fats that form cell membranes, as a cell divides.

To conduct this research, the scientists used a technique called infrared microspectrometry at Brookhaven's National Synchrotron Light Source, a facility that provides x-rays, ultraviolet light and infrared light for experiments in diverse scientific fields. This technique may open up a new area of investigation, which would reveal new information on the way a cell divides, grows, takes up food or drugs, and dies.

 

 

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