Corrosion Behavior of Hastelloy C-276 for Carbon-anode-based Oxide Reduction Applications

Jeon, Min Ku,Kim, Sung-Wook,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of Hastelloy C-276 was investigated to identify its applicability for carbon-anode-based oxide reduction (OR), in which Cl₂ and O₂ are simultaneously evolved at the anode. Under a 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar flow, the corrosion rate was less than 1 g·m^-2·h^-1 up to 500℃, whereas the rate increased exponentially from 500 to 700℃. The effects of the Cl₂-O₂ composition on the corrosion rate at flow rates of 30 mL·min^-1 Cl₂, 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂, and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ with a constant 170 mL·min^-1 Ar flow rate at 600℃ was analyzed. Based on the data from an 8 h reaction, the fastest corrosion rate was observed for the 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ case, followed by 30 mL·min^-1 Cl₂ and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂. The effects of the chlorine flow rate on the corrosion rate were negligible within the 5-30 mL·min^-1 range. A surface morphology analysis revealed the formation of vertical scratches in specimens that reacted under the Cl₂-O₂ mixed gas condition.

Ultrasonic Degradation of Endocrine Disrupting Compounds in Seawater and Brackish Water

So Young Park,Jong Sung Park,Ha Yoon Lee,Ji Yong Heo,Yeo Min Yoon,Kyung Ho Choi,Nam Guk Her 대한환경공학회 2011 Environmental Engineering Research Vol.16 No.3

In this study, a series of experiments was conducted on the relative degradation of commonly known endocrine-disrupting compounds such as bisphenol A (BPA) and 17α-ethinyl estradiol (Ee₂) in a single-component aqueous solution using 28 and 580 kHz ultrasonic reactors. The experiments were conducted with three different types of model water: deionized water (DI), synthetic brackish water (SBW), and synthetic seawater (SSW) at pH 4, 7.5, and 11 in the presence of inert glass beads and humic acids. Significantly higher sonochemical degradation (93-97% for BPA) occurred at 580 kHz than at 28 kHz (43-61% for BPA), regardless of water type. A slightly higher degradation was observed for Ee₂ compared to that of BPA. The degradation rate of BPA and Ee₂ in DI water, SBW, and SSW after 30 min of ultrasound irradiation at 580 kHz increased slightly with the increase in pH from 4 (0.073-0.091 min-1 for BPA and 0.081-0.094 min-1 for Ee₂) to 7.5 (0.087-0.114 min-1 for BPA and 0.092?0.124 min-1 for Ee₂). In contrast, significant degradation was observed at pH 11 (0.149-0.221 min-1 for BPA and 0.147-0.228 min-1 for Ee₂). For the given frequencies of 28 and 580 kHz, the degradation rate increased in the presence of glass beads (0.1 mm and 25 g) for both BPA and Ee₂: 0.018-0.107 min-1 without beads and 0.052-0.142 min-1 with beads for BPA; 0.021-0.111 min-1 without beads and 0.054-0.136 min-1 with beads for Ee₂. A slight increase in degradation of both BPA and Ee₂ was found as the concentration of dissolved organic carbon (DOC, humic acids) increased in both SBW and SSW: 0.107-0.115 min-1 in SBW and 0.087-0.101 min-1 in SSW for BPA; 0.111-0.111 min-1 in SWB and 0.092-0.105 min-1 in SSW for Ee₂. After 30 min of sonicating the humic acid solution, DOC removal varied depending on the water type: 27% (3 mg L-1) and 7% (10 mg L-1) in SBW and 7% (3 mg L-1) and 4% (10 mg L-1) in SSW.

가압가열 및 Microwave 처리가 생면의 품질에 미치는 영향

박시우,김꽃봉우리,김민지,강보경,박원민,김보람,박홍민,최정수,최호덕,안동현,Bark, Si-Woo,Kim, Koth-Bong-Woo-Ri,Kim, Min-Ji,Kang, Bo-Kyeong,Pak, Won-Min,Kim, Bo-Ram,Park, Hong-Min,Choi, Jung-Su,Choi, Ho-Duk,Ahn, Dong-Hyun 한국식품영양학회 2013 韓國食品營養學會誌 Vol.26 No.4

중력분을 이용하여 제면한 후 가압가열, microwave 및 가압가열과 microwave 병행 처리한 후, 생면 및 삶은 면의 품질에 미치는 영향에 대하여 알아보았다. 생면의 pH는 microwave 1 min 처리구에서 무처리구와 유의적인 차이를 보이지 않았으며, 수분 함량은 autoclave 50 min 처리구에서 무처리구와 유의적인 차이를 보이지 않았고, 그 외의 처리구에서는 모두 수분 함량이 감소함을 확인하였다. 면의 색도 측정 결과는 명도는 무처리구에 비해 모든 처리구에서 감소하였으며, 적색도는 microwave 1 min 처리구는 감소한 반면, 나머지 처리구는 증가하였다. 황색도는 autoclave 50 min 처리구와 autoclave 50 min/microwave 1 min 병행 처리구에서 증가한 반면, 나머지 물리적 처리구에서는 감소하였다. 삶은 면의 색도에서는 명도, 적색도, 황색도 모두에서 무처리구에 비하여 물리적 처리구에서 증가한 값을 나타내었다. 물성 측정 결과는 경도, 부착성, 응집성, 검성, 복원성에서 무처리구와 비교시 microwave 1 min 처리구는 유의적으로 감소하였으며, 그 외 처리구에서는 유의적으로 증가한 값을 나타내었다. 탄력성과 전단력은 모든 처리구에서 유의적으로 증가하였으며, 인장력은 가압가열 30 min 처리구와 무처리구가 유의적인 차이를 보이지 않았으나, 나머지 물리적 처리구에서는 유의적으로 증가하였다. 관능 평가 결과는 생면의 경우 색 항목에서 물리적 처리구들이 유의적으로 낮은 점수를 받았다. 맛, 질감, 향 항목에서는 무처리구와 물리적 처리구간 유의적 차이를 보이지 않았다. 전체적인 기호도에서는 microwave 1 min 처리구가 가장 높은 점수를 얻었으며, 가압가열(50 min)과 microwave(1 min) 병행 처리구는 무처리구와 비슷한 점수를 얻었다. 따라서 제면 후 가압가열 및 microwave 처리가 생면 및 삶은 면에 있어서 색과 질감 항목을 보완, 개선시킨다면 알러겐성이 저감화된 면을 제품화하는데 적합할 것으로 사료되어진다. This study was conducted to determine the effects of physical treatments for quality of wet noodles. Noodles were being tried with a microwave (for 1 min), an autoclave (for 30 or 50 min), and both autoclave and microwave (for 30/1 min or 50/1 min). The results showed that the pH levels were slightly decreased after treatments of autoclave and autoclave/microwave. The moisture contents were considerably decreased as compared to the control except autoclave (50 min). After all treatments, the lightness was decreased in all samples, but, redness was increased (except microwave) and the yellowness was increased after autoclave (50 min) and autoclave/microwave (50/1 min). Texture was increased as compared to the control except microwave. In the sensory evaluation, the noodles treated with microwave, autoclave (50 min), and autoclave/ microwave (50/1 min) showed a high score in overall preference. From these results, both the autoclave and microwave methods can be applied to the wet noodles without diminishing its quality to a great extent.

볶음 조건에 따른 발효 콩의 이화학적 특성 연구

유민정 ( Min Jung You ),최남순 ( Nam-soon Choi ) 한국식생활문화학회 2016 韓國食生活文化學會誌 Vol.31 No.6

This study was investigated the difference in the quality characteristics of the fermented soybean roasted with different conditions for making chungyukjang. Roasted condition of soybean was decided by pre-test, which was on 140°C for 21 min, 180°C 9.5 min, and 220°C 6 min. Fermented soybean with different roasted condition and conventionally made cheonggukjang were measured for proximate composition, color, pH, amino nitrogen, ammonia nitrogen, free sugar and amino acids. The lightness and yellowness of soybean fermented by conventional method was higher than those of the fermented soybean with roasted soybean. The contents of free sugar of fermented soybean roasted on 220°C for 6 min (FS220) was the highest among the group and followed by fermented soybean roasted on 180°C for 9.5 min (FS180), 140°C 21 min (FS140) and conventional cheonggukjang (FS0). The contents of total free amino acid was highest on fermented soybean roasted on 140°C for 21 min (FS140) and followed by fermented soybean roasted on 180°C for 9.5 min (FS180), 220°C 6 min (FS220) and conventional cheonggukjang (FS0).

Corrosion Behavior of Inconel X-750 for Carbon Anode Oxide Reduction Application

Jeon, Min Ku,Kim, Sung-Wook,Lee, Sang-Kwon,Choi, Eun-Young Korean Radioactive Waste Society 2020 방사성폐기물학회지 Vol.18 No.3

The corrosion behavior of the Inconel X-750 alloy was investigated for its potential application under a Cl₂-O₂ mixed gas flow in an Ar atmosphere. The corrosion rate was found to be negligible at temperatures up to 400℃ under a flow rate of 30 mL·min^-1 Cl₂ + 170 mL·min^-1 Ar, whereas an exponential increase was observed in the corrosion rate at temperatures greater than 500℃. The suppression of the corrosion reaction due to the presence of O₂ was verified experimentally at flow rates of 30 mL·min^-1 Cl₂ (4.96 g·m^-2·h^-1), 20 mL·min^-1 Cl₂ + 10 mL·min^-1 O₂ (2.02 g·m^-2 ·h^-1), and 10 mL·min^-1 Cl₂ + 20 mL·min^-1 O₂ (1.34 g·m^-2·h^-1) under a constant Ar flow rate of 170 mL·min^-1 at 600℃ for 8 h. The surface morphology analysis results revealed that porous surfaces with tunnel-type holes were produced under the Cl₂-O₂ mixed-gas condition. Furthermore, the effects of the Cl₂ flow rate on the corrosion rate were investigated, indicating that its impact was negligible within the range of 5-30 mL·min^-1 Cl₂ at 600℃.

물리적 처리에 의한 강력분 밀가루 Gliadin의 항원성 변화

강보경(Bo-Kyeong Kang),김꽃봉우리(Koth-Bong-Woo-Ri Kim),김민지(Min-Ji Kim),박시우(Si-Woo Bark),박원민(Won-Min Pak),김보람(Bo-Ram Kim),안나경(Na-Kyung Ahn),최연욱(Yeon-Uk Choi),최정수(Jung-Su Choi),최호덕(Ho-Duk Choi),안동현(Dong-Hyun A 한국식품영양과학회 2014 한국식품영양과학회지 Vol.43 No.4

본 연구에서는 가압가열 및 microwave 처리가 gliadin의 항원성에 미치는 영향을 살펴보기 위해 강력분에 가압가열과 microwave를 단독 또는 병행으로 처리하여 Ci-ELISA, SDS-PAGE 및 immunoblotting을 실시하였다. 가압가열 처리의 경우 시간이 길어질수록 IgG와의 결합력이 감소하였으며, 특히 50분 처리구에서 약 87%로 가장 낮은 결합력을 보였다. 또한 SDS-PAGE와 immunoblotting 결과에서도 무처리구에서 강하게 보였던 gliadin band가 가압가열처리에 의해 거의 소실되고 항체와 반응하지 않았다. 가압가열 및 microwave를 병행 처리 시도 마찬가지로 gliadin의 결합력이 감소하였으며, 처리구 중 가압가열 50분, microwave 5분 처리구에서 약 93%로 가장 낮은 결합력을 보였다. 반면 microwave를 단독으로 처리한 경우에는 일부 단백질의 변화는 관찰되었으나, 항원성 감소에는 효과가 없음을 확인하여 단백질 변화가 항원성에는 큰 효과를 준 것 같지 않다. 이상의 결과를 통해 가압가열 단독 처리 및 가압가열 및 microwave의 병행처리 시 gliadin의 항원성이 감소함을 확인하였다. This study was conducted to evaluate the effects of physical treatments on the antigenicity of gliadin in strong wheat flour. Strong wheat flour was treated with an autoclave (5, 10, 30, 50 min), a microwave (1, 5, 10 min), or both (10, 30, 50 min/ 5, 10 min), followed by SDS-PAGE, immunoblotting, and Ci-ELISA using anti-gliadin IgG. The results indicated that the binding ability of IgG to gliadin in strong wheat flour slightly decreased after autoclaving or autoclaving/microwaving. In particular, the binding ability was reduced to about 87% after autoclaving for 50 min and to 89% after autoclaving/microwaving (50/5 min). In addition, gliadin bands in the 50 min autoclaved group disappeared in both SDS-PAGE and immunoblotting. On the other hand, the antigenicity of gliadin was unaffected by microwaving alone. In conclusion, the results of this study suggest that autoclaving may reduce the antigenicity of gliadin in strong wheat flour.

가압가열 및 microwave에 의한 중력분 반죽 gliadin의 항원성 변화

곽지희(Ji-Hee Kwak),김꽃봉우리(Koth-Bong-Woo-Ri Kim),이청조(Chung-Jo Lee),김민지(Min-Ji Kim),김동현(Dong-Hyun Kim),선우찬(Chan Sunwoo),정슬아(Seul-A Jung),김현지(Hyun-Jee Kim),최정수(Jung-Su Choi),김성원(Seong-Won Kim),안동현(Dong-Hyun 한국식품과학회 2012 한국식품과학회지 Vol.44 No.1

본 연구에서는 가압가열 및 microwave 처리에 의한 중력분 반죽 추출물 내의 gliadin 단백질의 항원성 변화에 대해 살펴보았다. 중력분 반죽에 가압가열과 microwave를 단독 또는 병행으로 처리하여 ci-ELISA, SDS-PAGE 및 immunoblotting을 실시하였으며, 가압가열 처리에 의해서 anti-gliadin IgG 항체와 gliadin과의 결합력이 다소 감소한 것을 확인하였다. 특히 30 min 이상 처리시 더욱 감소한 것으로 나타났으며, SDS-PAGE와 immunoblotting 결과에서도 gliadin band의 강도가 약해지고 항체와의 반응도 나타나지 않았다. Microwave 처리의 경우, 5 min 이상 처리시 일부 gliadin 단백질의 소실이 관찰되었으나, 항원성에는 큰 변화가 없었다. 또한 가압가열 및 microwave 병행 처리에 의해 항원-항체 결합력이 더욱 감소되었으며, 특히 가압가열 50 min, microwave 10 min 처리시 약 35.0%로 감소되었다. 이상의 결과를 통해 가압가열 처리에 의해 중력분 반죽 추출물 내 gliadin의 항원성이 감소되는 것을 확인하였으며, microwave와 병행 처리하는 경우, 더욱 감소하는 것을 확인하였다. The aim of this study was to determine the optimal physical treatment to reduce the antigenicity of gliadin in wheat dough. Medium wheat dough was treated with an autoclave (5, 10, 30, and 50 min at 121℃, 1 atm), a microwave (1, 5, and 10 min) or both (10, 30, and 50 min/5, 10 min). The proteins in the dough extracts were analyzed by SDS-PAGE and the binding ability of anti-gliadin IgG to gliadin was examined by ci-ELISA and immunoblotting. Results showed that the ability of anti-gliadin IgG to bind to gliadin in wheat dough treated with an autoclave alone or in combination with a microwave was decreased. Especially, it declined to ~77% after autoclaving for 30 min and 35% after both autoclaving for 50 min and microwaving for 5 min. In addition, the intensity of gliadin bands in SDS-PAGE were weakened and anti-gliadin IgG did not recognize gliadin in immunoblotting. However, microwaving alone did not affect the antigenicity of gliadin in wheat dough. These results indicate that autoclaving may affect the reduction of the antigenicity of gliadin in medium wheat dough. Moreover, autoclaving in combination with microwaving is more effective for reducing the antigenicity of wheat dough.

모과내 기능성 유용성분 용매추출공정의 최적화

전주영 ( Ju Yeong Jeon ),조인희 ( In Hee Jo ),경현규 ( Hyun Kyu Kyung ),김현아 ( Hyun A Kim ),이창민 ( Chang Min Lee ),최용희 ( Yong Hee Choi ) 한국산업식품공학회 2010 산업 식품공학 Vol.14 No.2

본 연구에서는 모과내의 여러 가지 기능성 유용성분을 효과적으로 추출하기 위해서, 모과나무의 익은 열매로 만든 약재인 모과를 사용 하였다. 모과의 기능성 유용성분용매 추출 공정의 최적 조건을 확립하고자 하였다. 모과를 에탄올에 추출하여 반응표면 분석법으로 모니터링하여 최적 용매 조건을 설정하였다. 중심합성계획법에 따라 시료에 대한 용매비(X1)와 추출온도(X2), 추출시간(X3)을 요인변수로 하고 추출수율(Y1), 총페놀 함량(Y2), 전자공여능(Y3), 갈색도(Y4), 환원당(Y5)을 종속변수로 하여 시행하였다. 실험 결과 추출수율은 추출 온도와 추출 시간에 유의하게 영향을 받음을 알 수 있었다. 안장점에서 추출조건은 시료에 대한 용매비는 26.38mL/g, 추출온도는 72.82oC, 추출시간은 74.86 min에서 최대값을 나타내었다. 총페놀 함량은 용매비와 시간에 영향을 거의 받지 않았고 추출시간에는 영향을 받았으며, 최대값은 20.70mg/mL 로 나타났다. 이때의 추출조건은 시료에 대한 용매비는 22.61mL/g, 추출온도는 84.49oC, 추출시간은 77.25 min으로 나타났다. 전자공여능은 추출온도에 따라 유의하게 영향을 받은 것으로 나타났다. 안장점에서의 추출조건인 시료에 대한 용매비 10.65mL/g, 추출온도 67.78oC, 추출시간 96.75 min에서 추출수율은 94.12%로 예측되었다. 갈색도에 대한 추출조건은 시료에 대한 용매비 23.77mL/g, 추출온도 87.27oC, 추출시간 96.68 min 일 때 안장점이 나타났다. 환원당은 시료에 대한 용매비 26.83mL/g, 추출온도 82.167oC, 추출시간 81.94 min에서 10.55mg/mL로 최대값을 나타내었고 추출시간에 영향을 받았다. In this study, various active functional components in Chinese Quince were extracted by solvent extraction method. A central composit design for optimization was applied to investigate the effects of independent variables such as solvent to sample ratio (X1), extraction temperature (X2), and extraction time (X3) on the soluble solid contents (Y1), total phenols (Y2), electron donating ability (Y3), browning color (Y4) and reducing sugar contents (Y5). It was found that extraction temperature and extraction time were the main effective factors in this extraction process. The maximum soluble solid contents of 35.77% was obtained at 26.38mL/g (X1), 72.82oC (X2) and 74.86 min (X3) in saddle point. Total phenols were rarely affected by solvent ratio and extraction time, but it was affected by extraction temperature. The maximum total phenols of 20.70% was obtained at 22.61mL/g (X1), 84.49oC (X2), 77.25 min (X3) in saddle point. The electron donating ability was affected by extraction time. The maximum electron donating ability of 94.12% was obtained at 10.65mL/g (X1), 67.78oC (X2), 96.75 min (X3) in saddle point. The maximum browning color of 0.32% was obtained at 23.77mL/g (X1), 87.27oC (X2), 96.68 min (X3) in saddle point. The maximum value of reducing sugar content of 10.55% was obtained at 26.83mL/g (X1), 82.167oC (X2), 81.94 min (X3). Reducing sugar content was affected by extraction time.

崔致遠의 시를 통해 본 9세기 黃海航路

최낙민(Choi, Nack-Min) 한국해양대학교 국제해양문제연구소 2015 해항도시문화교섭학 Vol.0 No.12

海雲崔致遠(857∼?)은 9세기 바닷길을 통한 羅唐간의 문화교류를 대표하는 인물일 뿐만 아니라 한국 漢文學의 비조로 추앙받는 인물이다. 때문에 최치원에 대한 연구는 문학, 철학, 역사 등 다양한 방면에서 진행되어 많은 성과물을 내고 있다. 하지만 그의 행적을 해양실크로드와 연관시켜 진행한 연구는 그리 많지 않다. 다행히 최치원은 『桂苑筆耕集』卷20에 수록한 七言絶句15수와 七言律詩15수가 884년 10월 양주를 떠나 다음해 3월 신라의 왕도 경주에 도착하기까지 귀국길에 창작한 것임을 밝히고 있다. 본문에서는 최치원 선생의 『桂苑筆耕集』 뿐만 아니라 『孤雲集』?등에 수록된 작품 중, 귀국시기에 지어진 시를 분석하여 그가 이용한 황해항로를 살펴보고 시에 드러난 최치원의 심경을 살펴보았다. 먼저 황해항로의 西端揚州에서 중국 동해안에 이르는 大運河길을 통해 귀국을 즈음한 최치원의 복잡한 심경과 함께 강남지역의 사회상을 살펴보았다. 다음으로는 항해에 필요한 순풍을 기다리기 위해 한겨울을 바닷가에서 보냈던 최치원의 시를 통해 항해에 종사하는 사람들의 종교와 삶을 유추하였다. 마지막 장에서는 황해항로에 대해 고찰하고 慶州의 모습을 통해 바닷길을 통한 문화교류의 양상을 살펴보았다. 이를 통해 경제적인 측면이 강조된 남양해양실크로드와 달리 신라와 당을 연결하는 황해해로의 특징은 문화교류에 있었음을 확인할 수 있었다. Choi Chi Won(857∼?), also known by his pen names as Haeun and Goun, is not only a person who represents the cultural exchange between the two dynasties, the Silla-Tang (羅唐) through the Sea Route in the ninth century, but also one of the most revered figures as the progenitor of Sino-Korean literature (漢文學) in Korea. For this reason, the studies on Choi Chi Won are being carried out and have achieved a number of products in various fields, such as literature, philosophy, and history. There is, however, only few works conducted on his deeds in connection with the Maritime Silk Road. Fortunately, Choi Chi Won expressed that the poems in his twenty-volume work, 『桂苑筆耕集』Gyewon Pilgyeonjip : Plowing the Gassia Grove with a Writing Brush were composed during the return voyage from the time he left Yangzh?u (?州) in October of the year 884 to the time he arrived at Gyeongju, the capital of the Silla Dynasty in March of the next year. Those poems are fifteen verses written in quatrain with seven chinese characters in each line (七言絶句) and the other fifteen poems which includes eight-line verse with seven-chinese characters each (七言律詩). This thesis explores the Yellow Sea Route that Choi Chi Won made a voyage on and how his mind was expressed in his poems by analyzing his poetry written during the homecoming. The analysis includes 『孤雲集』 The collection of Goun’s poetical work as well as 『桂苑筆耕集』Gyewon Pilgyeonjip, in the body. At first, it aims to read Choi’s complicated emotions around the time when he returned back home through the Grand Canal on the Yellow Sea Route from the western end of Yangzh?u linking to the eastern coast of China. It also endeavors to dissect social aspects in the southern region of the Yangtze River. Furthermore, religions and the lives of the people engaged in navigation will be analogized through Choi’s poetry which was composed on the seaside as he waited for a tailwind to continue his voyage. In the last chapter, the modality of the cultural exchange through the Maritime Silk Road is explored by contemplating the Yellow Sea Route and Gyeongju. From this work, it is assured that the main characteristic of the Yellow Sea Route, connecting the Silla and Tang Dynasties, is the cultural exchange which is different from the South Sea-Maritime Silk Road in which economic aspects are emphasized.

A Comparative Experimental Study of the, In-vitro Efficiency of Hypertonic, Saline-Enhanced Hepatic Bipolar and, Monopolar Radiofrequency Ablation

Lee, Jeong Min,Han, Joon Koo,Kim, Se Hyung,Sohn, Kyu Li,Lee, Kyoung Ho,Ah, Su Kyung,Choi, Byung Ihn Korean Radiological Society 2003 Korean Journal of Radiology Vol.4 No.3