{'fraction_non_alphanumeric': 0.013468013468013467, 'fraction_numerical': 0.006734006734006734, 'mean_word_length': 5.257894736842105, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Fast Fourier Transform Analysis of Images of Scanning Electron Microscope of Porous Anodic Alumina

In this study, Fast Fourier Transform (FFT) analysis was conducted on the images of scanning electron microscope of morphology of the porous anodic alumina formed on high purity aluminium. High purity aluminium substrates were anodized at 50 V in 0.3 M oxalic acid of 15°C for 60 minutes. As anodized porous anodic alumina were then subjected to oxide dissolution treatment of increasing exposure duration, up to three minutes. Micrographs were captured by using scanning electron microscope and the images were analyzed using FFT. It was found that the FFT images of as anodized porous anodic alumina and porous anodic alumina subjected to oxide dissolution treatment up to two minutes were similar, which were disc shaped white forms, indicating no ordered periodic structures were formed. When porous anodic alumina subjected to oxide dissolution treatment for three minutes, FFT image showed six distinct spots at the edges of a hexagon, indicating a perfect hexagonal pore arrangement was obtained for porous anodic alumina subjected to oxide dissolution treatment for three minutes.