FRACTAL ANALYSIS ON PORE STRUCTURE FOR ACTIVATED CARBON-FIBERS

Recently, the active carbon filter (ACF) has drawn attention because of its usefulness in the electrical and electronics fields. To improve the quality of ACF, the microscopic structure of this material must be analyzed. One method is to observe the structure using a transmission electron microscope (TEM). Recently, the capability of the TEM has been improved drastically. Not only can its molecular structure be observed but also numerous analytical equipment has been attached to it. ACF has been investigated by using a TEM, and it has been found that the ACF structure was so complex that quantitative analysis was impossible. Computer analysis of a TEM image has also been attempted. In this analysis, the TEM image was processed by the two-dimensional fast Fourier transform and frequency analysis to investigate the distribution of the pore diameter of ACF. As a result, it was speculated that the pore shape was fractal. Then, it was shown that the contour of the pore cross section was fractal and the fractal dimension was obtained. When the structure was too complex to analyze only by TEM analysis, the introduction of the image processing method was effective.