{'fraction_non_alphanumeric': 0.02852485737571312, 'fraction_numerical': 0.0032599837000814994, 'mean_word_length': 5.395833333333333, '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}}
Organic Material Analysis of a Lacquered Wooden Sheath of Long Sword with Ring Pommel Excavated in Imdang Ancient Tomb

In order to examine the constituents and weathered state of a lacquer specimen, analysis of the organic materials was conducted using py/GC/MS(pyrolysis-gas chromatography-mass spectrometry). The samples were obtained from the lacquered wooden sheath of a long ring-pommel sword excavated in the Imdang No.1 ancient tomb constructed around the Proto-Three Kingdoms period. In direct py/GC/MS, the sample and the dried Asian lacquer showed similar chromatograms, while the characteristic compounds of Asian lacquer such as 1,2-dimethoxy-3-pentadecylbenzene were observed in THM(thermally assisted hydrolysis and methylation)-py/GC/MS. In addition, compounds like dimethyl nonanedioate, which presumably originated from drying oil, were also detected. Furthermore, the detection of oxidized catechols in considerable amount indicated that the degradation of lacquer is estimated to result from the oxidation of urushiol. Therefore, it is suggested that the lacquered wooden sheath was prepared using Asian lacquer and drying oil, and that the lacquer layer was considerably oxidized over the long burial time.