Congressional Affairs | Newsroom | Speeches | Priority Areas | What's Cool | Publications | Partners | History | About Us

   You are in: NSF Home > OLPA Home > Newsroom > Archives > News Tips: Previous Years > November 5, 2001

November 5, 2001

For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Peter West

Contents of this News Tip:

• SCIENTISTS PREDICT NEW STRUCTURES FOR WATER ICE
• ARECIBO NAMED A HISTORIC ENGINEERING LANDMARK
• MACARTHUR FOUNDATION HONORS NSF RESEARCHERS

Scientists Predict New Structures for Water Ice

A research team partially funded by the National Science Foundation (NSF) predicts that water frozen within minute carbon tubes will form previously unknown crystal structures. The insight into how water behaves on a nanometer (one billionth of a meter) scale may affect the next generation of nanoelectronic devices, biochips, and studies of how water shapes proteins. Using computer modeling and thermodynamic analyses, researcher Xiao Cheng Zeng, of the University of Nebraska-Lincoln, and his colleagues in Japan and the United States, simulated the crystallization of ice within the confined space of a carbon nanotube. Allowed to grow only lengthwise, slight increases in tube diameter resulted in four new tubular ice structures: square (the smallest), pentagonal, hexagonal, and heptagonal (the largest). The researchers also predicted that the nearly one-dimensional environment could yield a solid-liquid "critical point," a condition beyond which the liquid and solid phases of water would merge into one supercritical phase. That condition had only been previously seen -- in any substance -- at transitions between liquids and gasses. Because the findings show how water operates within tiny, confined pores, future studies may help reveal how water interferes with carbon-nanotube semiconductors. The findings may also guide research to shrink current microtube devices, such as machines that deposit DNA onto biochips. Water is also critical in binding proteins together and helping them to maintain their shape. Understanding the role of water at the scale of protein molecules will help researchers understand the structures and properties of these biological building blocks. [Josh Chamot]

The above images show how water may crystallize within a carbon nanotube. The large spheres are oxygen atoms, small spheres are hydrogen atoms, short bars are covalent bonds within individual water molecules, and long bars are hydrogen bonds between separate water molecules. The image on the top shows a disordered array of water molecules as they would appear if confined within a 1.11 nanometer carbon nanotube. The image on the bottom shows the same molecules after being frozen within the tube, yielding an elongate ice tube with a square cross-section. The cross-section consists of four water molecules, with the oxygen atoms positioned at each corner. Graphic credit: Dr. Xiao Cheng Zeng of the University of Nebraska-Lincoln

Top of Page 

Arecibo Named a Historic Engineering Landmark

	Photo credit: courtesy of the NAIC-Arecibo Observatory, a facility of the NSF, and David Parker/Science Photo Library.

Two nationally prominent professional organizations have designated NSF's Arecibo Observatory in Puerto Rico as a landmark in the history of engineering.

The American Society of Mechanical Engineers recently named Arecibo a Historical Mechanical Engineering Landmark. The Institute of Electrical and Electronics Engineers named the observatory a Milestone in Electrical Engineering. Joseph Bordogna, NSF's deputy director, accepted the joint honors at the observatory on November 3.

The massive radio antenna, which boasts a receiver dish 305 meters (1000 feet) wide, is the world's largest radio astronomy facility. Designed by William Gordon, formerly of Cornell University, its construction and operation led to electrical engineering advances in antenna design, signal processing and electronic instrumentation.

In mechanical engineering, Arecibo produced advances in antenna suspension and drive systems. The drive system positions the enormous antenna with millimeter precision.

Arecibo has produced discoveries about Earth's ionosphere and astronomical objects such as planets outside of our solar system, pulsars and near-Earth asteroids. [Amber Jones]

For more information about Arecibo, see: www.naic.edu

Top of Page

MacArthur Foundation Honors NSF Researchers

A chemist, an optical physicist and an astrophysicist who have received support from NSF's Directorate for Mathematical and Physical Sciences were recently awarded MacArthur Foundation Fellowships.

The three are among 23 people who earned the $500,000 awards this year from the Chicago-based John D. and Catherine T. MacArthur Foundation.

The five-year unrestricted grants - often colloquially called "genius grants" -- are made to those in public science, science, the arts and academia with outstanding track records of talent, creativity and accomplishments.

Brooks Pate, a physical chemist at the University of Virginia, advanced the field of high-energy chemistry by overcoming significant technical obstacles to apply spectroscopy techniques to probe the chemical reactions of excited molecules.

Optical physicist Lene Hau of Harvard University has examined the interactions between light and matter, including the capacity to control or even stop light. With NSF funding, she has explored the properties of light interacting with a Bose-Einstein condensate, advancing the field of quantum optics.

David Spergel of Princeton University, an astrophysicist, has tackled research into the origins, structure and evolution of the universe. His findings have contributed to scientists' understanding of dark matter, galaxies and other large-scale structure in the universe. [Amber Jones]

Top of Page

 
National Science Foundation
Office of Legislative and Public Affairs
4201 Wilson Boulevard
Arlington, Virginia 22230, USA
Tel: 703-292-8070
FIRS: 800-877-8339 | TDD: 703-292-5090