Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Breakthrough! UNC scientists’ research promises improved X-ray machines using carbon nanotubes

02.07.2002


The basic technology that produces X-rays has remained essentially the same for a century, but now scientists and physicians at the University of North Carolina at Chapel Hill and Applied Nanotechnologies Inc. say they should be able to improve it significantly.



Experiments the team conducted have shown they can cause carbon nanotubes, a new form of carbon discovered about a decade ago, to generate intense electron beams that bombard a metal "target" to produce X-rays. Researchers say they have demonstrated that their cold-cathode device can generate sufficient X-ray flux to create images of extremities such as the human hand.

The advantage of using carbon nanotubes is that machines incorporating them can work at room temperature rather than the 1500 or so degrees Celsius that conventional X-ray machines now require and produce.


"If this works as well as we think it will, we can make such machines a lot smaller and cooler and be able to turn them on and off much faster," said Dr. Otto Z. Zhou, associate professor of physics and materials sciences. "Other advantages are that they should be cheaper, be safer in terms of the lower heat generated, last longer, use less electricity and produce higher resolution images.

"We believe we have made a major breakthrough in X-ray technology, and we are extremely excited about it."

A report on their experiments appears in the July 8 issue of Applied Physics Letters, a science and technology journal. Patents on the UNC work are pending.

Besides Zhou, authors are Dr. Guo Z. Yue, a former UNC faculty member now with United Solar Systems; Qi Oiu and Drs. Bo Gao and Hideo Shimoda of Applied Nanotechnologies Inc., students Yuan Cheng and Jian Zhang, and Dr. Jian Ping Lu, associate professor of physics and astronomy and applied and materials sciences. Dr. Sha Chang, associate professor of radiation oncology at the UNC School of Medicine, also participated in the project.

"Scientists and others, including the popular press, have shown a lot of interest in carbon nanotubes because of numerous potential applications," Zhou said. "They are very strong tubular structures formed from a single layer of carbon atoms and are only about a billionth of a meter in diameter."

In the past, UNC scientists and others have used carbon nanotubes to produce electrons, he said. What’s new is that until now, no one could generate enough electrons to create distinct images like conventional X-rays do. Nanotubes replace traditional metal filaments that must be heated to high temperatures before being subjected to an electric field. The tubes shed electrons easily because, being so small, they are extremely sharp.

"We already have taken pictures of human hands and fish that are as good as standard X-rays," Zhou said. "We think our images eventually will be clearer than conventional ones since we have a more pointed, tunable source of electrons. That would help doctors, for example, get more useful information from pictures of broken bones, for example."

The physicists are working with manufacturers to turn their discovery into working machines and expect to have them on the market within a year or two, he said.

Being able to miniaturize X-ray devices could have more major benefits, Zhou said, including allowing technicians to take X-rays inside or outside ambulances before ever leaving the scenes of accidents. No major technical obstacles remain in their way.

In addition, the new X-ray technology will allow manufacturing of large-scale X-ray scanning machines for industrial inspections, airport security screening and customs inspections.

Other uses of carbon nanotubes include flat panel display and telecommunications devices, fuel cells, high-strength composite materials and novel molecular electronics for the next generation of computers, he said. People have raised the possibility of using them to improve batteries, but no one demonstrated that they might work better than conventional materials until Zhou and his UNC team published a paper on the subject in January in Physical Review Letters.

That paper showed they could potentially improve electric batteries by using single-wall carbon nanotubes to help store electrical charges. They have patented the process of creating such nanotubes.


Zhou directs the N.C. Center for Nanoscale Materials at UNC. Applied Nanotechnologies Inc., which seeks to develop new industrial and medical applications for carbon nanotubes, is a new spin-off company resulting from his group’s work. Support for the experiments came from the Office of Naval Research and private sources.

Note: Zhou can be reached at (919) 962-3297 or Zhou@email.unc.edu
Contact: David Williamson, (919) 962-8596

David Williamson | EurekAlert!

More articles from Physics and Astronomy:

nachricht Beyond the brim, Sombrero Galaxy's halo suggests turbulent past
21.02.2020 | NASA/Goddard Space Flight Center

nachricht 10,000 times faster calculations of many-body quantum dynamics possible
21.02.2020 | Christian-Albrechts-Universität zu Kiel

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A step towards controlling spin-dependent petahertz electronics by material defects

The operational speed of semiconductors in various electronic and optoelectronic devices is limited to several gigahertz (a billion oscillations per second). This constrains the upper limit of the operational speed of computing. Now researchers from the Max Planck Institute for the Structure and Dynamics of Matter in Hamburg, Germany, and the Indian Institute of Technology in Bombay have explained how these processes can be sped up through the use of light waves and defected solid materials.

Light waves perform several hundred trillion oscillations per second. Hence, it is natural to envision employing light oscillations to drive the electronic...

Im Focus: Freiburg researcher investigate the origins of surface texture

Most natural and artificial surfaces are rough: metals and even glasses that appear smooth to the naked eye can look like jagged mountain ranges under the microscope. There is currently no uniform theory about the origin of this roughness despite it being observed on all scales, from the atomic to the tectonic. Scientists suspect that the rough surface is formed by irreversible plastic deformation that occurs in many processes of mechanical machining of components such as milling.

Prof. Dr. Lars Pastewka from the Simulation group at the Department of Microsystems Engineering at the University of Freiburg and his team have simulated such...

Im Focus: Skyrmions like it hot: Spin structures are controllable even at high temperatures

Investigation of the temperature dependence of the skyrmion Hall effect reveals further insights into possible new data storage devices

The joint research project of Johannes Gutenberg University Mainz (JGU) and the Massachusetts Institute of Technology (MIT) that had previously demonstrated...

Im Focus: Making the internet more energy efficient through systemic optimization

Researchers at Chalmers University of Technology, Sweden, recently completed a 5-year research project looking at how to make fibre optic communications systems more energy efficient. Among their proposals are smart, error-correcting data chip circuits, which they refined to be 10 times less energy consumptive. The project has yielded several scientific articles, in publications including Nature Communications.

Streaming films and music, scrolling through social media, and using cloud-based storage services are everyday activities now.

Im Focus: New synthesis methods enhance 3D chemical space for drug discovery

After helping develop a new approach for organic synthesis -- carbon-hydrogen functionalization -- scientists at Emory University are now showing how this approach may apply to drug discovery. Nature Catalysis published their most recent work -- a streamlined process for making a three-dimensional scaffold of keen interest to the pharmaceutical industry.

"Our tools open up whole new chemical space for potential drug targets," says Huw Davies, Emory professor of organic chemistry and senior author of the paper.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

70th Lindau Nobel Laureate Meeting: Around 70 Laureates set to meet with young scientists from approx. 100 countries

12.02.2020 | Event News

11th Advanced Battery Power Conference, March 24-25, 2020 in Münster/Germany

16.01.2020 | Event News

Laser Colloquium Hydrogen LKH2: fast and reliable fuel cell manufacturing

15.01.2020 | Event News

 
Latest News

Active droplets

21.02.2020 | Medical Engineering

Finding new clues to brain cancer treatment

21.02.2020 | Health and Medicine

Beyond the brim, Sombrero Galaxy's halo suggests turbulent past

21.02.2020 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>