Mini X-ray tubes could revolutionize radiotherapy — and airport baggage scanners. Carbon nanotubes can be used to generate X-rays.Pasieka / Science Photo Library It's taken more than a century, but X-rays are finally getting a shake-up. A new way of generating them uses carbon nanotubes and could allow real-time three-dimensional scanning. "If you look at current imaging technology, technically very little has changed since Wilhelm Röntgen discovered X-rays more than 100 years ago," says materials scientist Otto Zhou at the University of North Carolina (UNC) in Chapel Hill. Zhou and his colleagues first came up with their novel alternative to...