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 X-ray photoelectron spectroscopy under real ambient pressure conditions
28.06.2017 | National Institutes of Natural Sciences

nachricht New photoacoustic technique detects gases at parts-per-quadrillion level
28.06.2017 | Brown University

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

High conductive foils enabling large area lighting

29.06.2017 | Power and Electrical Engineering

Designed proteins to treat muscular dystrophy

29.06.2017 | Life Sciences

Climate Fluctuations & Non-equilibrium Statistical Mechanics: An Interdisciplinary Dialog

29.06.2017 | Seminars Workshops

VideoLinks
B2B-VideoLinks
More VideoLinks >>>