Makoto Fujie

X-ray Visualization of Carbon-Particle Oxidation Process in Supercritical Water

A real-time X-ray visualization system for low X-ray absorption materials has been developed. The system is mainly composed of a multi-color scintillator based image intensifier and a real-time image-processing unit. The color image intensifier has such advantages as the high sensitivity, the wide dynamic range and the long lifetime over the conventional one. The dynamic imaging of low X-ray absorption materials was realized by the video-rate image subtraction function of the image processor. The system has been successfully applied for an observation of a carbon-particle oxidation process in supercritical water. The low X-ray absorption difference between carbon and supercritical water, surrounded by high X-ray absorption metal wall, is one of the most difficult objects to get good image. In our system, the carbon-particle image was taken at a 30 frame/sec video-rate by continuously subtracting the background image until at the instance of the carbon-particle disappearance by oxidation.