Fabrication of Carbon Nanotube Field Emitters Using a Dip-Coating Method

Song, Y. I.,Kim, G. Y.,Choi, H. K.,Jeong, H. J.,Kim, K. K.,Yang, C.-M.,Lim, S. C.,An, K. H.,Jung, K. T.,Lee, Y. H. WILEY-VCH Verlag 2006 CHEMICAL VAPOR DEPOSITION -WEINHEIM- Vol.12 No.6

<P>A simple and robust dip-coating method for fabricating carbon nanotube (CNT) field emitters has been proposed. The thin multiwalled (tMW)CNTs synthesized by CVD were dispersed in various solutions such as N,N-dimethylformamide (DMF), isopropyl alcohol (IPA), N-methyl-2-pyrrolidinone (NMP), and dichloroethane (DCE). The weak adhesion between CNTs and substrate, a serious drawback of the dip-coating approach, was resolved by anchoring CNTs to the substrate via the melting of an indium layer. We found that the uniformity and density of the CNTs could be optimized by controlling the degree of dispersion of CNTs in solvents. The field-emission characteristics are also discussed.</P> <B>Graphic Abstract</B> <P>Carbon nanotube field emitters are synthesized using a dip-coating method. It was found that CNTs were best dispersed in dimethylformamide, showing optimum vaporization conditions for dip-coating. By controlling the number of dipping times, uniformly CNT-coated films are obtained (see Figure) that possess the maximum field-enhancement factor and a low turn-on voltage. </P>

Sandy Sediment Transport Mechanism on Tidal Sand Bodies, West Coast of Korea : 한국 서해 만경강·동진강 하구 해역

Park,Yong Ahn,Kang,Hyo Jin,Song,Y.I. 韓國海洋大學校 附設 海洋科學技術硏究所 1992 硏究論文集 Vol.1 No.1

조류가 강한 만경강-동진강 부근의 연안역에는 많은 사주들이 잘 발달하여 있다. 그 중 한 사주에서 측정된 조류는 그 최대유속이 밀물과 썰물 사이에 심한 비대칭 현상을 나타낸다. 사주의 남쪽 측면에서는 밀물이 우세하고 북쪽 측면에서는 썰물이 우세한 이러한 비대칭성은 대조시 유속이 강할 때 더욱 뚜렷이 나타난다. 또한 남쪽의 밀물 우세 현상은 북쪽의 썰물 우세 현상 보다 더욱 강하게 나타나고 있어 사주는 전체적으로 밀물에 의하여 더 큰 영향을 받고 있다. 모래로 이루어진 이 지역의 해저 퇴적물들은 대부분 조류에 의해 밑짐으로 이동되고 있으며, 이러한 조류의 비대칭성으로 인하여 모래는 어느 한 방향으로 순 이동이 일어나게 된다. 이러한 모래의 순 이동은 남쪽에서는 해안쪽으로 북쪽에서는 외해쪽으로 이동하여 바닥의 모래는 사주를 반시계 방향으로 순환하는 양상을 띄게 될 것이며 전체적으로는 강한 밀물의 영향으로 사주가 해안쪽으로 이동하는 결과를 가능하게 할 것이다. 사주의 남쪽부분의 형태가 불규칙적이고 V자 모양을 나타내는 것도 이러한 강한 밀물의 영향을 반영하는 것으로 해석된다. Sand bars associated with strong tidal currents are well developed in the subtidal zone near the Kokunsan islands. Tidal currents measured at sand bar in the area show an asymmetry in magnitude between flood and ebb currents. At the southern flank of the sand bar the currents are flood-dominant whereas the currents are ebb-dominant at the northern flank. The asymmetry is more distinctive as the currents become stronger during spring tide. Moreover, the flood-dominance along the southern flank is stronger than the ebb-dominance along the northern flank. Thus the flood current is more affective to the sand bar. The sandy bottom sediment is mostly transported as bedload by the tidal currents. The magnitude asymmetry of the tidal currents results in a net sediment movement in one direction. The direction is onshore in the south and offshore in the north, which may result in a net counterlookwise rotation of the sands around the sand bar. However, the sand bar may migrate towards onshore due to the more affective flood current in the south. The irregular V-shaped outline of the sand bar in the south also seem to reflect the strong effect of flood current.

Determination of Polyphenol Components of Korean Prostrate Spurge ( <i>Euphorbia supina</i> ) by Using Liquid Chromatography—Tandem Mass Spectrometry: Overall Contribution to Antioxidant Activity

Song, Yi,Jeong, Sung Woo,Lee, Won Sup,Park, Semin,Kim, Yun-Hi,Kim, Gon-Sup,Lee, Soo Jung,Jin, Jong Sung,Kim, Chi-Yeon,Lee, Ji Eun,Ok, Se Yun,Bark, Ki-Min,Shin, Sung Chul Hindawi Publishing Corporation 2014 Journal of analytical methods in chemistry Vol.2014 No.-

<P>The Korean prostrate spurge <I>Euphorbia supina</I> is a weed that has been used in folk medicine in Korea against a variety of diseases. Nine polyphenols were characterized for this plant by using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and the results were compared with the literature data. The individual components were validated using the calibration curves of structurally related external standards and quantified for the first time by using the validated method. Correlation coefficients (<I>r</I><SUP>2</SUP>) were >0.9907. The limit of detection and limit of quantification of the method were >0.028 mg/L and 0.094 mg/L, respectively. Recoveries measured at 50 mg/L and 100 mg/L were 76.1–102.8% and 85.2–98.6%, respectively. The total amount of the identified polyphenols was 3352.9 ± 2.8 mg/kg fresh plant. Quercetin and kaempferol derivatives formed 84.8% of the total polyphenols. The antioxidant activities of the flavonoids were evaluated in terms of 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation-scavenging activity, and the reducing power showed a dose-dependent increase. Cell viability was effectively suppressed at polyphenol mixture concentrations >250 mg/L.</P>

대학생의 부모 자녀 간 의사소통과 스마트폰 중독의 관계에서 생활스트레스와 다차원적 경험회피의 매개효과

지송이 ( Ji¸ Song Yi ),김보영 ( Kim¸ Boyoung ) 안암교육학회 2021 한국교육학연구 Vol.27 No.3

본 연구는 대학생을 대상으로 부모 자녀 간 의사소통과 스마트폰 중독의 관계에서 생활스트레스와 다차원적 경험회피의 매개효과를 검증하여 스마트폰 중독의 개입을 위한 시사점을 제시하고자 하였다. 이를 위해 4년제 대학교에 재학 중인 만 19세~만24세 대학생 394명을 대상으로 설문을 실시하였다. 수집된 자료는 SPSS 26.0과 SPSS PROCESS Macro 3.5를 사용하여 기술통계 및 상관분석을 실시하고 다차원적 경험회피 하위요인의 병렬매개분석과 생활스트레스와 다차원적 경험회피의 이중매개효과를 확인하였으며, 연구의 결과는 다음과 같다. 첫째, 부모 자녀 간 의사소통, 생활 스트레스, 다차원적 경험회피, 스마트폰 중독간에는 모두 유의한 상관관계가 나타났다. 둘째, 생활스트레스와 스마트폰 중독의 관계에서 다차원적 경험회피의 매개효과와 하위요인 가운데 지연행동의 매개효과가 확인되었다. 셋째, 부모 자녀 간 의사소통과 스마트폰 중독의 관계에서 생활스트레스와 다차원적 경험회피의 이중매개효과와 생활스트레스와 지연행동의 이중매개효과가 검증되었으며 지연행동을 투입한 모형이 전체 수준의 다차원적 경험회피 변인 대비 높은 설명력을 보였다. 이러한 결과를 토대로 스마트폰 중독의 개입에 관한 시사점과 본 연구의 제한점, 후속연구를 위한 제언을 제시하였다. This study tried to suggest implications for smartphone addiction intervention by examining the mediating effects of life stress and multidimensional experience avoidance in the relationship between parent-child communication and smartphone addiction for university students. For this purpose, a questionnaire survey was conducted on 394 university students aged 19 to 24. The collected data were analyzed using SPSS 26.0 and SPSS PROCESS Macro 3.5. The results of this study were as follows. First, there were significant correlations among communication between parents and children, life stress, avoidance of multidimensional experiences, and smartphone addiction. Second, The mediating effect of multidimensional experience avoidance between life stress and smartphone addiction was confirmed and the mediating effect of delayed behavior among the sub-factors of multidimensional experience avoidance was also confirmed. Third, in the relationship between parent-child communication and smartphone addiction, the double-mediating effect of life stress and multidimensional experience avoidance and the double-mediating effect of life stress and delayed behavior were verified. In addition, the explanatory power of delayed behavior was high compared to the multidimensional experience avoidance. Based on these results, the implications for intervention of smartphone addiction, limitations of this study, and suggestions for follow-up studies are presented.

집단 음악치료가 ADHD 아동의 자기표현과 자아상에 미치는 효과

문송이 ( Moon¸ Song-yi ),남현우 ( Nam¸ Hyun-woo ) 한국아동교육학회 2021 아동교육 Vol.30 No.4

본 연구는 주의력 결핍 및 과잉행동 장애(ADHD) 아동을 대상으로 집단 음악치료 프로그램을 실시하여 자기표현과 자아상에 미치는 효과를 알아본 것이다. 연구대상은 ADHD로 진단을 받은 초등학교 2-3학년 아동 3명이며, 40분씩 주 2회, 16회기 동안 집단 음악치료 프로그램을 실시하였다. ADHD 아동의 자기표현과 자아상에 미치는 효과를 파악하기 위해 회기별 행동 변화와 사전/사후검사인 그림검사 변화 분석을 했다. 연구 결과, 집단 음악치료 프로그램이 ADHD 아동의 자기표현과 자아상에 긍정적인 효과를 보이는 것으로 나타났다. 본 연구는 주의집중과 충동성에 초점을 맞춘 대부분의 선행 연구들과는 달리 ADHD 아동의 자기표현과 긍정적 자아상 형성을 위해 집단 음악치료 프로그램을 적용하고 효과를 밝혔다는 데 의의가 있다. 학령기 ADHD 아동의 학교생활을 비롯한 다양한 사회적응 문제를 해결하기 위해 자기표현과 자아상에 긍정적인 향상을 도모하는 음악치료 프로그램이 유용하게 활용될 수 있기를 기대해 본다. The purpose of this study is to investigate the effect of group music therapy program on self-expression and self-image for children with attention deficit/hyperactivity disorder(ADHD). The 3 elementary school children diagnosed with ADHD were conducted in the group music therapy program, for 40 minutes, 2 times a week, for 16 sessions. To analyze the effect on children's self-expression and self-image, analysis by session and self-image test were used. As a result of the study, it was found that the self-expression and self-image of children with ADHD after the group music therapy program had a positive effect. Unlike most previous studies focusing on attention and impulsiveness, this study is meaningful in that it applied and revealed a group music therapy program for self-expression and positive self-image formation of ADHD children. It is hoped that a music therapy program that promotes positive improvement in self-expression and self-image of school-age ADHD children will be usefully used to solve various social adaptation problems including school life.

Applications of cryogenic method to water vapor sampling from ambient air for isotopes analysis

Songyi Kim,Yeongcheol Han,Soon-Do Hur,Jeonghoon Lee 한국분석과학회 2017 학술대회논문집 Vol.2017 No.11

Pretreatment of lignocellulose using recycled ionic liquid for enzymatic saccharification

( Songyi Han ),( Soyeon Kim ),( Seonngmin Ji ),( Chanwoo Park ),( Hyunwoo Namgung ),( Pureunnarae Seo ),( Seunghwan Lee ) 韓國木材工學會 2016 한국목재공학회 학술발표논문집 Vol.2016 No.2

Ionic liquids is known to have many merits in view of green chemistry, such as high thermal stability, non-volatility, non-flammability, low melting points, excellent dissolution ability compared with volatile organic solvents. With these advantages, ionic liquids have been used as new green solvents in various biorefinery research fields, especially for the pretreatment of lignocellulosic biomass to improve enzymatic saccharification. Especially, 1-ethyl-3-methyl imidazolium acetate ([EMIM]Ac) has been known to be effective for the dissolution of total lignocellulose components. However, ionic liquids are generally more expensive than other organic solvents, which remains a problem to be solved. This study was carried out to investigate how may times [EMIM]Ac) can be reused for the pretreatment, not losing its effectiveness.

The Exploration of Solo Dining Experience in South Korea

Songyi Han 한국서비스경영학회 2017 한국서비스경영학회 학술대회 Vol.2017 No.7

Phytochemical and Mineral Contents of Crepidiastrum denticulatum Subjected to Different Air Anion Levels

Songyi Park,Jihoon Bae,Sanmin Kim,Myungmin Oh 한국원예학회 2017 한국원예학회 학술발표요지 Vol.2017 No.5

F-31 The prognosis of lung cancer in patient with idiopathic pulmonary fibrosis according to treatment modality

( Songyi Han ),( Youlim Kim ),( Yeonjoo Lee ),( Jong Sung Park ),( Young-jae Cho ),( Ho Il Yoon ),( Jae Ho Lee ),( Choon-taek Lee ),( Sang Hoon Lee ) 대한결핵 및 호흡기학회 2017 대한결핵 및 호흡기학회 추계학술대회 초록집 Vol.124 No.-

Background: There were evidences that IPF is one of the important risk factor of lung cancer (LC) and as time passes after the diagnosis of IPF. In this study, we aim to find out what treatments are associated with a better prognosis for LC patients with IPF. Method: From 2003 to 2016, a total of 299 patients with both IPF and LC were searched by the diagnostic name in the Seoul National University Bundang hospital. 168 patients were included in the analysis except for other form of ILD, infection (n=13), other malignancy (n=11), and missing data (n=102). Among the patients, 21 were conservative therapy, 66 were surgery, 69 were chemotherapy, and 6 were treated for radiation therapy as primary treatment. GAP score was calculated with gender, age, FVC, and DLCO as Ley et al. reported. Results: The average age was 69.9 years and the men were dominant (92.9%). The overall survival rate was high in surgery (p<0.001; HR, 0.144) and chemotherapy (p=0.046; HR, 0.487). Surgery (p=0.014; HR, 0.244) increased the survival rate in the lung cancer stage I, II, and IIIa, and chemotherapy (p<0.001; HR, 0.168) and surgery (p=0.003; HR, 0.033) improved the survival rate in the IIIb and IV, compared to the conservative care. The survival rate was improved by surgery (p<0.001; HR, 0.132) in GAP stage I and was increased by chemotherapy (p = 0.007; HR, 0.145) in stages II and III. Conclusion: Although the motality of IPF-associated LC is higher than lung cancer only, it seems to be effective for surgery or chemotherapy depending on the lung cancer or IPF stage.