플라스틱 광섬유용 클래드 재료 개발 - PMMA/THV 블렌드의 상용성과 계면 접착력 -

박은주,박인철,이무성,박민,Park, Eun-Ju,Park, In-Cheol,Lee, Moo-Sung,Park, Min 한국섬유공학회 2008 한국섬유공학회지 Vol.45 No.6

We investigated the miscibility of poly(methyl methacrylate) (PMMA) and random copolymers of tetrafluoroethylene-hexafluoropropylene-vinylidene fluoride (THV) blends and their interfacial adhesion as part of the development of cladding materials for PMMA based plastic optical fiber. Three different types of THV with different copolymer composition were used as candidates for them. PMMA/THV blends being melt-mixed at $240^{\circ}C$ showed typical immiscible morphology and the glass transition temperatures of the component polymers did not change after mixing. However, tie chains connecting matrix and dispersed phase were identified when THV with high content of vinylidene fluoride, i.e., THV220 was used. In spite of the intrinsic immiscibility of PMMA/THV blends the interfacial adhesion obtained from peel test was above $10^4N/m^2$ at the adhesion temperature of $240^{\circ}C$ and increased with increasing the temperature for THV220. From the melt viscosity data of the polymers it was recommended that the extrusion temperature of THV should be higher than that of PMMA in order to obtain smooth interface between core and cladding layer.

경기 일부지역 초등학교에서 담임교사의 영양교육 실시와 3~6학년생의 식생활지침 준수 정도

박은주,강현주,송경희,박경애,이홍미,Park, Eunjoo,Kang, Hyunjoo,Song, Kyung Hee,Park, Kyung Ae,Lee, Hongmie 대한영양사협회 2020 대한영양사협회 학술지 Vol.26 No.2

Homeroom teachers are not usually nutrition professionals, but they spend a lot of time with students in elementary school classrooms. This study was conducted to determine the association of homeroom teachers' nutrition education with the dietary habits of their classroom children. The subjects were 131 homeroom teachers and their 1,102 children from 17 elementary schools in Gyeonggi, Korea. Self-administered questionnaires to collect information on dietary habits were conducted in December 2016. The dietary habits were determined with the adherences to the Dietary Guidelines for Adults and Children, respectively, by coding the better diet life with a higher score. The significances between groups according to teachers' implementation of nutrition education (106 implemented, 25 not implemented) were analyzed by using SPSS at P<0.05. Implementing nutrition education was not associated with the dietary habits of teachers themselves, but their students. Therefore, the students of teachers who implemented nutrition education had significantly higher adherence to 8 items out of 19 items (P<0.05, P<0.01). More of the students considered themselves as non-picky eaters (P<0.05), tried to eat all the foods served at school lunch even when it contained unwanted ingredients (P<0.01), and agreed on the need of nutrition education (P<0.01), as compared to their counterparts. Conclusively, this study suggests that nutrition education delivered by homeroom teachers may be associated with more desirable dietary habits of students, even though homeroom teachers are not nutrition professionals. Therefore, efforts should be undertaken to develop and provide proper contents for homeroom teachers to use in nutrition education for elementary students.

Effects of Paecilomyces tenuipes Cultivated in Egg Yolk on Lipid Metabolism in Rats on a High Fat-Cholesterol Diet

박은주,Sang Mong Lee,Nam Sook Park,진병래,Han-Seok Kang,Jee Hyung Jung 한국식품영양과학회 2006 Journal of medicinal food Vol.9 No.2

We investigated the effects of the fruiting bodies of cultivated Paecilomyces tenuipesgrown on egg yolk (PTE)on lipid and antioxidant metabolisms. Forty 8-week-old male Sprague-Dawley rats were fed a high fat/high cholesterol diet(control) or a high fat/high cholesterol diet with 1%, 3%, or 5% PTE for 5 weeks. PTE was found to significantly lower plasmatotal lipid, total cholesterol, low-density lipoprotein cholesterol, and the atherogenic index, compared with the control. He-patic total lipid and total cholesterol were also significantly lower than in the control group. The hypolipidemic activity ofPTE was increased with increasing concentrations, and plasma lipid peroxidation was significantly lower in the 3% and 5%PTE groups than in the control or 1% PTE group. Plasma total radical trapping antioxidant potential, erythrocytic antioxidantenzyme, and leukocytic DNA damage were not significantly different among the groups. Our results indicate that P. tenuipescultivated on egg yolk can improve lipid profiles and lipid peroxidation in rats fed a high fat/high cholesterol diet.

고내열 POF용 클래딩 재료 제조 (II) -Methacrylic Acid 공단량체 첨가 효과-

박은주,정민진,김진봉,이무성,박민,Park, Eun-Ju,Jung, Min-Jin,Kim, Jin-Bong,Lee, Moo-Sung,Park, Min 한국섬유공학회 2004 한국섬유공학회지 Vol.41 No.2

We introduced methacrylic acid (MAA) into 80/20 trifluoroethyl methacrylate (TFEMA)-methyl methacrylate (MMA) copolymer in order to prepare heat-resistant cladding materials for plastic optical fiber based on poly(methyl methacrylate) (PMMA). As the content of MAA in the terpolymers increases, their T$_{g}$s increase to be higher values than those predicted by the Fox equation. Moreover, the interfacial adhesion between PMMA and the terpolymers, evaluated from the cross cut tape test, also increases from 1B to 4B classification. The results show that the MAA units, introduced in order to induce a specific intermolecular interaction, effectively contribute to increase the interfacial adhesion with PMMA as well as the thermal stability of the resultant copolymers.s.

《난경(難經)》 오사론(五邪論)을 적용한 침법(鍼法)이 2K1C 고혈압(高血壓) 백서(白鼠)의 혈압(血壓)에 미치는 영향(影響)

박은주,나창수,윤여충,조명래,Park, Eun-ju,Na, Chang-su,Yun, Yeu-chung,Cho, Myung-rae 대한침구의학회 2003 대한침구의학회지 Vol.20 No.1

Objectives : The purpose of this study is to compare Xingjian(LR2) Shaofu(HT8) with Dadun(LR1) Shaofu(HT8) on Blood Pressure in Hypertensive RAT induced by Two Kidney One Clip(2KIC). Methods : This experiments was to investigate the effects of LR2 HT8(originated from ${\ll}$Classic on Difficulty${\gg}$ Shi Ze Xie Qi Zi), LR1 HT8(originated from ${\ll}$Ling Shu${\gg}$ Sheng Ze Xie Zhi) acupuncture on the blood pressure, cardiomegalic index, and plasma levels of atrial natriuretic peptide in hypertensive rat induced by 2K1C. Results: 1. Blood pressure was decreased significantly after third acupuncture of LR2 HT8. 2. Blood pressure was decreased significantly after acupuncture of LR2 HT8, but was increased after LR2 HT8. 3. Cardiomegalic index was not changed after acupuncture of LR2-HT8 and LR1-HT8 4. Plasma levels of atrial natriuretic peptide was increased significantly after acupuncture of LR2 HT8 but LR1 HT8 was not changed.

우리아파트 녹색아파트-서울하계동 한신동성아파트

박은주,Park, Eun-Ju 에너지절약전문기업협회 2007 esco Vol.47 No.-

6개동 498세대가 거주하고 있는 서울 하계동 한신동성아파트는 지난 2006년 12월 327kW급 열병합발전기를 도입했다. 기존에 스팀보일러로 중앙난방을 하던 방식에서 발전기로 대체한 이 아파트는 가동한지 7개월만에 2억 원 이상 비용절감을 하고 있다. 한신동성아파트를 찾아가 보았다.

가족과 함께 탁구를...

박은주,Park, Eun-Ju 한국건강관리협회 1991 건강소식 Vol.15 No.2

ESCO탐방-LIG엔설팅

박은주,Park, Eun-Ju 에너지절약전문기업협회 2007 esco Vol.48 No.-

2002년도에 ESCO사업을 시작한 LIG엔설팅(전 티알씨코리아, 대표 최승기)은 발주자지만 에너지관리공단 진단용역을 통한 전문성 강화와 유능한 인재로 단기간 ESCO시장의 선두권에 진입하고 있다. 특히 이번에는 LIG엔설팅으로 사명을 바꾸고 본격적인 시장 공략에 나서고 있다.

유체 내 전기선폭발법에 의한 은 나노입자 유체의 제조 및 특성

박은주,김지순,권영순,김진천,최혜선,정용훈,Park, E.J.,Bac, L.H.,Kim, J.S.,Kwon, Y.S.,Kim, J.C.,Choi, H.S.,Chung, Y.H. 한국분말야금학회 2009 한국분말재료학회지 (KPMI) Vol.16 No.3

This paper presents a novel single-step method to prepare the Ag nanometallic particle dispersed fluid (nanofluid) by electrical explosion of wire in liquid, deionized water (DI water). X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM) and transmission electron microscope (TEM) were used to investigate the characteristics of the Ag nanofluids. Zeta potential was also used to measure the dispersion properties of the as-prepared Ag nanofluid. Pure Ag phase was detected in the nanofluids using water. FE-SEM analysis shows that the size of the particles formed in DI water was about 88 nm and Zeta potential value was about -43.68 without any physical and chemical treatments. Thermal conductivity of the as-prepared Ag particle dispersed nanofluid shows much higher value than that of pure DI water.

고온히터 솔더접합부의 신뢰성 평가 및 예측

박은주,권대일,사윤기,Park, Eunju,Kwon, Daeil,Sa, Yoonki 한국마이크로전자및패키징학회 2017 마이크로전자 및 패키징학회지 Vol.24 No.2

본 논문에서는 고온히터의 주 고장 원인이 되는 단자대 솔더 접합부의 손상 원인을 파악하여 사용 수명을 예측하는 방법을 제시하였다. 고온 히터 사용에 따르는 온도 스트레스로 인한 단자대 솔더 접합부의 영향을 알아보기 위해 동일한 부하 조건을 재현할 수 있는 고온히터 시편을 제작하였다. 고온히터 단자대의 단락은 주로 솔더접합부 내의 금속간 화합물이나 void로 인한 crack발생에서 기인한다. 가속시험을 통한 고장 재현을 위해 고온히터 시편을 $170^{\circ}C$의 오븐에서 장시간 동안 노출시키며 솔더 내부의 금속간 화합물 조성과 void의 변화를 측정하였다. 솔더 내의 금속간 화합물 층의 변화를 확인하기 위해서 주사전자현미경을 이용한 단면 분석을 시행하였고, 시편의 온도 스트레스로 인한 void 변화를 측정하기 위해 저항분광법을 이용한 특정 기준 주파수와 위상에 대한 신호를 실시간으로 측정하는 동시에 microCT를 이용하여 void 분율을 간헐적으로 관찰하였다. 시험결과 고온 노출 시간이 증가함에 따라 솔더 내부의 void의 분율이 증가하는 것을 확인하였으며 위상차 변화와 높은 상관관계가 있음을 확인하였다. 이 상관관계를 통해 온도 스트레스에 노출된 고온히터의 수명을 비파괴적으로 예측할 수 있음을 제시하였다. This paper proposes an approach to predict the reliability of high temperature heaters by identifying their primary failure modes and mechanisms in the field. Test specimens were designed to have the equivalent stress conditions with the high temperature heaters in the field in order to examine the effect of stress conditions on the solder joint failures. There failures often result from cracking due to intermetallic compound (IMC) or void formation within a solder joint. Aging tests have been performed by exposing the test specimens to a temperature of $170^{\circ}C$ in order to reproduce solder joint failures in the field. During the test, changes in IMC formation were investigated by scanning electron microscopy (SEM) on the cross-sections of the test specimens, while changes in void formation were monitored both by resistance spectroscopy and by micro-computed tomography (microCT), alternately. The test results demonstrated the void volume within the solder increased as the time at the high temperature increased. Also, the phase shift of high frequency resistance was found to have high correlation with the void volume. These results implied the failure of high temperature heaters can be non-destructively predicted based on the correlation.