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        검색결과 5

        1.
        2022.06 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Heavy bitumen scattered in the underground sedimentary layer is a kind of unconventional energy source, and by extracting it, a production well is excavated in the sedimentary layer and high-temperature and high-pressure steam is injected to reduce the viscosity of bitumen and recover it to the ground steam assisted method is applied. As a recovery method that uses the steam effect of the dilution effect of solvent injection, it is a recovery method that can increase thermal efficiency. In this study, the process system of the central processing facility(CPF) of the hybrid steam-solvent recovery method that injects solvent into the existing steam assisted method was analyzed, and the core facilities for each process were identified, and hybrid steam-solvent recovery compared to the existing steam assisted method. In the case of the method, it was evaluated that the amount of steam supply and all utility costs decreased according to the solvent injection.
        4,000원
        2.
        2019.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Temperature distribution studies were performed in steam-air retort to investigate the influence of various processing conditions (come-up time, sterilization temperature, and internal pressure throughout the steam-air retort). Retort temperature data were analyzed for temperature deviations during holding phase, maximum temperature difference between test locations at the beginning and after 1, 3, and 5 min of the holding phase, and box-and-whiskers plots for each location during the holding phase. The results showed that high sterilization temperature led to a more uniform temperature distribution than low sterilization temperature (pasteurization). In pasteurization condition, the temperature stability was slightly increased by increasing pressure during the holding phase. On the other hand, the temperature stability was slightly decreased in high sterilization temperature condition. Programming of the comeup phase did not affect the temperature uniformity. In addition, the slowest cold spot was found at the bottom floor during the holding phase in all conditions. This study determined that the temperature distribution is affected by retort processing conditions, but the steam-air retort needs more validation tests for temperature stability.
        4,000원
        3.
        2018.05 서비스 종료(열람 제한)
        Background : The major components in Astragalus membranaceus are isoflavonoids, triterpene and polysaccharides. Also, isoflavonoids was composed to aglycon and glucoside derivatives. In this study, we performed fermentation process (enzyme treatment) and steam processing (high temperature and pressure) to increase aglycon such as formononetin and calycosin. Methods and Results : The steam processing was performed at a lot of conditions, such as temperature (80, 100, 120℃) and time (30, 60 and 120 min). Fermentation processing carried out by A. membranaceus extract fermented with microorganisms which have high β -glucosidase activity (selection by esculin agar method) for detached glucose from isoflavonoids, converted to algycon. The isoflavonoids were analyzed using high pressure liquid chromatography (HPLC) in fermentation product of A. membranaceu extract by treated with steam processing at various conditions. As a result of β-glucosidase activity by pNP assay, we selected three strains, Pediococcus pentosaceus, Weissella cibaria and Saccharomyces cerevisiae. Isoflavone aglycon was the highest in fermentation product by S. cerevisiae for 3 days, but change of isoflavonoids was not observed in steam processing. The calycosin-glucoside and ononin were reduced in fermentation product of A. membranaceus extract, whereas calycosin and formononetin was increased. Conclusion : This results showed that isoflavone glycoside converted to isoflavone aglycon in A. membranaceus by fermentation process, it seems to be available for industrial use.
        4.
        2018.04 KCI 등재 서비스 종료(열람 제한)
        Background: Hot steaming is known to be effective in improving the biological activities of plant extracts by breaking down useful compounds to low molecular weight ones. Methods and Results: This study aimed to develop an optimal extraction and steam processing method for enhancing the low molecular ginsenoside contents of the adventitious roots culture of wild mountain ginseng. The total ginsenoside was optimally extracted when 70% EtOH was used at 50℃, whereas low molecule ginsenoside such as Rg2, Rh1, Rh4 and Rk1 could be extracted using 70% EtOH at 70℃. The adventitious roots culture of wild mountain ginseng is known to contain four major ginsenosides, i.e., Rb2, Rb1, Rg1 and Rd, however new ginsenosides Rg6, Rh4, Rg3, Rk1 and Rg5 were new abundantly obtaind after steam processing method was applied. The contents of total ginsenosides were the highest when thermal steam processing was conducted at 120℃ for 120 min. Unlike ginsenosides such as Rg1, Re, Rb1, Rc, Rb2, and Rh1, which decreased after steam processing, Rg3, Rk1, and Rg5 increased after thermal processing. Steam processing significanltly reduced the content of Rb1, increased that of Rg6 by about ten times than that in the adventitious roots culture of wild mountain ginseng. Conclusions: Our study showed that the optimal extraction and steam processing method increased the content of total ginsenosides and allowed the extraction of minor ginsenosides from major ones.