http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
( Sumin Pyo ),( Hanie Hakimian ),( Young-min Kim ),( Kyung-seun Yoo ),( Young-kwon Park ) 한국공업화학회 2021 공업화학 Vol.32 No.6
In the current research, thermal and catalytic thermogravimetric (TG) analysis of polyethylene terephthalate (PET) over natural zeolite (NZ), olivine, bentonite, HZSM-5, and HAl-MCM-41 were investigated using a TG analyzer and model-free kinetic analysis. Catalytic TG analysis of PET was carried out at multi-heating rates, 10, 20, 30, and 40 °C/min, under nitrogen atmosphere. Apparent activation energy (Ea) values for the thermal and catalytic pyrolysis of PET were calculated using Flynn-Wall-Ozawa method. Although natural catalysts, NZ, olivine, and bentonite, could not lead the higher PET decomposition efficiency than synthetic zeolites, HZSM-5 and HAl-MCM-41, maximum decomposition temperatures on the differential TG (DTG) curves for the catalytic pyrolysis of PET, 436 °C over olivine, 435 °C over bentonite, and 434 °C over NZ, at 10 °C/min, were definitely lower than non-catalytic pyrolysis. Calculated Ea values for the catalytic pyrolysis of PET over natural catalysts, 177 kJ/mol over olivine, 168 kJ/mol over bentonite, and 171 kJ/mol over NZ, were also not lower than those over synthetic zeolites, however, those were also much lower than the thermal decomposition, suggesting their feasibility as the proper and cost-effective catalysts on the pyrolysis of PET.
Sumin Shin,Pyo Won Park,Woo-Sik Han,Ki Ick Sung,Wook Sung Kim,Young Tak Lee 대한흉부외과학회 2011 Journal of Chest Surgery (J Chest Surg) Vol.44 No.6
Left ventricular (LV) hypertrophy caused by aortic valve stenosis (AS) leads to cardiovascular morbidity and mortality. We sought to determine whether aortic valve replacement (AVR) decreases LV mass and improves LV function. Materials and Methods: Retrospective review for 358 consecutive patients, who underwent aortic valve replacement for degenerative AS between January 1995 and December 2008, was performed. There were 230 men and 128 women, and their age at operation was 63.2±10 years (30∼85 years). Results: There was no in-hospital mortality, and mean follow-up duration after discharge was 48.9 months (2∼167 months). Immediate postoperative echocardiography revealed that LV mass index and mean gradient across the aortic valve decreased significantly (p<0.001), and LV mass continued to decrease during the follow-up period (p<0.001). LV ejection fraction (EF) temporarily decreased postoperatively (p<0.001), but LV function recovered immediately and continued to improve with a significant difference between preoperative and postoperative EF (p<0.001). There were 15 late deaths during the follow-up period, and overall survival at 5 and 10 years were 94% and 90%, respectively. On multivariable analysis, age at operation (p=0.008), concomitant coronary bypass surgery (p<0.003), lower preoperative LVEF (<40%) (p=0.0018), and higher EUROScore (>7) (p=0.045) were risk factors for late death. Conclusion: After AVR for degenerative AS, reduction of left ventricular mass and improvement of left ventricular function continue late after operation.
Primary copper-associated chronic hepatitis without COMMD1 mutation in a Dalmatian: a case report
Sumin Yun,Dohee Lee,Jimin Oh,Yeon Chae,Taesik Yun,Yoonhoi Koo,Mhan-Pyo Yang,Byeong-Teck Kang,Hakhyun Kim 대한수의학회 2022 大韓獸醫學會誌 Vol.62 No.4
A 12-year-old intact male Dalmatian dog presented hyporexia and vomiting for 1 week. Blood analysis revealed increased liver enzyme activity. Histopathological examination of the liver confirmed chronic hepatitis with fibrosis and necrosis. Copper staining revealed marked copper accumulation (2,770 ppm; normal range, 200 to 400 ppm), prominent in the centrilobular region, and compatible with copper-associated chronic hepatitis. However, copper metabolism domain containing 1 (COMMD1) mutation predisposing to copper accumulation in the liver tissue was not identified. The dog received medications but died 1 month after first visit. This is the first case of primary copper-associated hepatitis without COMMD1 mutation in a Dalmatian dog in South Korea.
Layer-by-Layer Assembly of Free-Standing Nanofilms by Controlled Rolling
Kang, Sumin,Pyo, Jae-Bum,Kim, Taek-Soo American Chemical Society 2018 Langmuir Vol.34 No.20
<P>A water surface not only provides a habitat to many living organisms but also opens up new possibilities to develop state-of-the-art technologies. Here, we show a technology for the layer-by-layer assembly of free-standing nanofilms by controlled rolling. The water surface is exploited as an ideal platform for rolling a nanofilm, allowing adhesion control and frictionless feeding. The nanofilm floating on the water surface is attached to a tube by van der Waals adhesion and is rolled up by the rotation of the tube. This method can assemble diverse film materials including metals, polymers, and two-dimensional materials, with an easy control of the number of layers. Furthermore, heterogeneous and spiral structures of the nanofilm are achieved. Various applications such as a stretchable tubular electrode, an electroactive polymer tube actuator, and a superelastic nanofilm tube are demonstrated. We believe this work can potentially lead to a breakthrough in the nanofilm assembly processes.</P> [FIG OMISSION]</BR>
항공용 가스터빈 연소기에서의 혼합기 노즐 형상의 단순화가 음향장 해석 결과에 미치는 영향
표영민,홍수민,김대식,Pyo, Yeongmin,Hong, Sumin,Kim, Daesik 한국분무공학회 2019 한국액체미립화학회지 Vol.24 No.2
A 3D FEM (Finite Element Method) based Helmholtz solver has been commonly used to characterize fundamental acoustic behavior and investigate dynamic instability features in many combustion systems. In this approach, a geometrical simplification of the target system has been generally made in order to reduce computational time and cost because a real combustor and fuel nozzle have a very complicated flow passage. The feasibility of these simplifications is quantitatively investigated in a small aero gas turbine nozzle in term of acoustic characteristics. It is found that the simplification in a nozzle geometry during the 3D FEM analysis process has no great influence on the acoustic modeling results, while the calculation complexity can be improved for a similar modeling accuracy.
Catalytic pyrolysis of waste printed circuit boards
( Hyunjin Kim ),( Jihyeon Seo ),( Haneul Shim ),( Youngeun Kang ),( Young-min Kim ),( Sumin Pyo ),( Young-kwon Park ) 한국폐기물자원순환학회 2022 ISSE 초록집 Vol.2022 No.-
Owing to the increased amount of electrical and electronic equipment, caused by the usage amount increase and further accelerated the exchange period of hardware, such as personal computer, smart phone, display equipment, and so on, the amount of electronic waste (e-waste) had been largely increased in recent decades. Printed circuit board (PCB) is a main component of electrical and electronic equipment and difficult to be recycled due to its harmful effect caused by the high halogen contents. In addition, the multilayer structure of PCB, consisted with additives, polymers, paper, and inorganics, makes it difficult to use the simple pyrolysis product as fuel or chemical feedstocks. Therefore, the catalytic pyrolysis was applied to increase the selectivity toward to the value-added products in this study. For the experiments, the tandem micro reactor-gas chromatography/mass spectrometry was used for the simple pyrolysis in the 1<sup>st</sup> furnace and sequential catalytic upgrading of pyrolysis products in the 2<sup>nd</sup> furnace. The product distribution produced at different temperature and by the use of different catalysts was analyzed and discussed to optimize the process operation for the chemical recycling of PCB. The obtained results suggested that the product oil quality can be increased by applying catalytic pyrolysis process increasing the yield of aromatic hydrocarbons with the decrease oxygen contents.