• Biotechnology and Bioprocess Engineering:BBE
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• 제9권3호
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• pp.179-183
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• 2004

A biocompatible polyelectrolyte complex multilayer (PECML) film consisting of poly-L-lysine (PLL) as a polycation and hyaluronic acid (HA) as a polyanion was developed to test its use for surface modification to prevent cell attachment and protein drug delivery. The formation of PECML through the electrostatic interaction of HA and PLL was confirmed by contact angle measurement, ESCA analysis, and HA content analysis. HA content increased rapidly up to 8 cycles for HA/PLL deposition and then slightly increased with an increasing number of deposition cycle. In vitro release of PLL in the PECML continued up to 4 days and ca. 25% of HA remained on the chitosan-coated cover glass after in vitro release test for 7 days. From the results, PECML of HA and PLL appeared to be stable for about 4 days. The surface modification of the chitosan-coated cover glass with PECML resulted in drastically reduced peripheral blood mononuclear cell (PBMC) attachment. Concerned with its use for protein drug delivery, we confirmed that bovine serum albumin (BSA) as a model protein could be incorporated into the PECML and its release might be triggered by the degradation of HA with hyaluronidase.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 추계학술대회 논문집 학회본부A
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• pp.248-252
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• 1998

The ACE Engineering, Inc. (ACE) of Seoul, Korea and The Energy Systems Institute (SEI) of Irkutsk, Russia has extensively studied the formation of an interconnected electric power systems throughout the North Eastern Asia Region(NEAR). The region encompasses East Siberia (ESR), Far East of Russia(FER), North East China(NEC), Mongolia(MON), North Korea(NKOR), South Korea(SKOR). Although geographically adjacent to each other, these countries and territories have different levels and rates of economic development, possess different reserves of energy resources which complement each other and hence, can interact to their mutual benefits. This Project is called Peace Network Project (PNP) because it seems to contribute for development of power economy and clean environment. In a word, the PEACE Network is expected to serve as "Power Economy And Clean Environment Network" and to promote the international cooperation. to expedite the peaceful reunification of North & South Korea and to revive the Korean culture in the North, and eventually contribute to the human prosperity.

• Journal of Photoscience
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• 제2권1호
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• pp.7-11
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• 1995

Powders of artificial crystallites of titanium(IV) oxide, TiO$_2$(B), were synthesized by the calcination of tetratitanic acid (hydrate, $H_2Ti_4O_9H_2O$; TTA). The relating titanates, potassium octatitanate ($K_2Ti_8O_{17}$) and octatitanic acid($H_2Ti_8O_{17}$), were also prepared. These powders, loaded with small amount of Pt, were suspended in an aqueous solution of 2-propanol and irradiated under argon atmosphere at 298 K + 0.5 deg. All the photocatalysts tested in this study produced almost equimolar amount of acetone and molecular hydrogen (H$_2$). Among them TiO$_2$(B) and TYA showed the higher photocatalytic activity but rather lower than commercial titanium(IV) oxide (TiO$_2$) powders. The photocatalytic activity of TiO$_2$(B) for 2-propanol dehydrogenation in deaerated aqueous suspension increased with the elevating calcination temperature. Comparison of rate of H$_2$ formation from methanol and 2-propanol solutions by the TiO$_2$(B) photocatalyst suggested a possibility of selection of substrate with its molecular size by TiO$_2$(B)

• 공업화학
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• 제34권3호
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• pp.213-220
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• 2023

혼합기질막(mixed-matrix membrane, MMM)은 고성능 충전제가 고분자 기질에 분산된 구조로, 지난 30년간 이를 이용한 기체분리 연구가 집중적으로 수행되었다. 일반적으로 MMM은 고분자 막보다 우수한 기체 분리 성능을 가지고 있으며, 다결정 막에 비해 좋은 확장성을 보인다. 그러나 이러한 잠재성에도 불구하고, MMM의 상용화는 여러 가지 어려운 문제들로 인해 지연되고 있다. MMM의 주요 문제 중 하나는 충전제와 고분자 사이의 부적절한 계면 상호작용으로 결함(즉, 개면 공극 등)이 형성될 수 있다는 것이다. 따라서 많은 MMM 연구에서 이러한 계면의 문제를 해결하기 위한 전략이 제시되었다. 하지만 계면상의 상호작용으로 MMM이 가진 문제점들을 해결하려는 과학적 접근에 비해 손쉽고 효과적으로 대면적의 MMM을 제조하기 위한 공학적 접근은 상대적으로 간과되어 왔다. 본 총설에서는 MMM의 대면적화를 위한 공학적인 접근 중 하나인 고분자 변형을 통해 가능해진 금속-유기 골격체(metal-organic framework, MOF)의 원위치 형성을 이용한 MMM 제막 방법을 소개하고자 한다. 이 새로운 제막법은 현재 MMM이 직면하고 있는 문제들을 공학적인 접근으로 효과적으로 해결하여 MMM의 상용화를 촉진시킬 수 있다.

• 전기화학회지
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• 제16권3호
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• pp.162-168
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• 2013

$Li_2MnO_3-LiMO_2$(M=Ni, Co, Mn) 나노 복합체는 높은 이론 용량을 가지고 있어 전기 자동차용 2차 전지 활물질 재료로 많은 연구가 진행되고 있다. 하지만 $Li_2MnO_3-LiMO_2$(M=Ni, Co, Mn)로부터 250 mAh/g 이상의 용량을 구현하기 위해서는 4.4 V 이상의 구동전압이 필요하며, 이러한 높은 구동 전압은 전지의 수명 및 고온 방치 특성의 저해 요소로 작용하고 있다. 본 연구에서는 이러한 문제점을 개선하기 위해서 FEC (Fluoroethylene carbonate), 플루오로알킬 에테르, $LiPF_6$가 주성분인 신규 전해액(F-based EL)을 설계하였다. F-based EL은 1.3 M $LiPF_6$ EC/EMC/DMC (3/4/3, v/v/v) (STD) 대비 안정한 SEI를 형성하며, 산화 안정성이 뛰어나 $Li_2MnO_3-LiMO_2$(M=Ni, Co, Mn)/graphite 셀의 수명 및 방치 중 가스 저감에 효과가 있음을 확인할 수 있었다.

• 한국조경학회지
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• 제20권2호
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• pp.90-105
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• 1992

the purpose of this study is to suggest objective basic daa for park management proposal through the quantitative analysis of users' behaviours and satisfaction for the actual conditions of management in Chonju neiborhood parks. For this, users' behaviors and socio-ecnomic characteristics have been anlyzed. Specificaly, it atempts to investigate users' anticipation and degree of satisfaction applied Expectancy Theory by Likert scale. And users' satisfaction for the actual conditions of management had been analyzed by using the multiple regression. Results of this study can be summarized as follow; From the aspect of utilization reality, the male usage was slightly higher than female usage, and the usage rate among the young and students such as high school students or university students also appeared slightly higher than the norm. Due to the fact, subject park had been neighborhood parks, walking usage was predominant, and the length of stay to be less than an hour. Generally, the values of users' post occupancy evaluation were lower than those of anticipated, in well known parks. In landscape satisfaction level, the parks with harmonious visual element had high landscape evaluation, and each category showed diversity depending on the park. Seasonableness, formation of physical elements, visual uniqueness, cozy atmosphere appeared as main explicatory variables having positive effects on the satisfaction level for the landscape. According to the multiple regression analysis, the major variables to the satisfaction for the actual condition of vegetation managements were harmony with facilities, recovery of artificial injury. In the park facilities and operation, the major variables related to the satisfaction were conditions of management of rest equip, facilities and guidance of use, observe the rules, respectively.

• Clinical and Experimental Pediatrics
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• 제49권5호
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• pp.565-569
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• 2006

Rothmund-Thomson 증후군은 상염색체 열성질환으로 다형피부증(poikiloderma), 희박한 모발과 눈썹, 저신장, 골격계 이상, 유소년기 백내장과 악성종양의 위험이 높은 것으로 특징지어지는 증후군이다. 골격계의 이상은 RTS 환아의 68%에서 보고되었고 신체전반의 골격계 이형성으로 형성부전이나 기형으로 나타난다. 요골형성부전, 엄지손가락 저형성, 골감소증, 슬개골 저형성이나 슬개골 형성 부전 등이 보고되어 있다. 흔치 않은 증상으로는 말안장코와 삼각형의 얼굴 등이 보고되어있다. RTS에서 골육종을 포함한 악성종양의 발생빈도가 높고 면역학적 이상이 보고되어 있다. 피부종양이 가장 흔하며 상피세포암, 기저세포암, Bowen's disease 등이 있고 두 번째로는 육종이 흔하다. 저자들은 전신적으로 혈관확장 및 과색소침착을 보이는 다형 피부 소견과 함께 요골형성부전, 척골기형, 엄지손가락형성부전, 슬개골 형성부전의 골격계 기형이 있으면서 이후 좌측 경골에 골육종이 발생한 Rothmund-Thomson 증후군을 경험하였기에 보고하는 바이다.

• Journal of Photoscience
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• 제1권1호
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• pp.31-37
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• 1994

Photoirradiation at > 300 nm onto a suspension of platinized TiO$_2$ (TiO$_2$-Pt) particles in an aqueous solution. of N$_{\varepsilon}$-carbamyI-L-lysine (Lys(CONH)$_2$) induced the selective N-cyclization of Lys(CONH$_2$) into almost optically pure L-pipecolinic acid (PCA) under argon atmosphere at ambient temperature. Among various TiO$_2$-Pt catalysts, a P-25 (Degussa) powder platinized via impregnation from chloroplatinic acid followed by hydrogen reduction at 753 K exhibited the highest photocatalytic activity for Lys(CONH$_2$) consumption and L-PCA production. GC-MS analyses of L-PCA obtained photocatalytically from $^{15}$N$\alpha$-Lys(CONH$_2$) revealed the selective formation $^{15}$N-substituted L-PCA. This implies that the mechanism for L-PCA production contains selective cleavage of C$_{\varepsilon}$-N bond and intramolecular alkylation at $\alpha$-amino group. Effect of pH on the rate of this photocatalytic reaction was investigated in detail and compared with the pH-dependent charge distribution in Lys(CONH$_2$) molecule. It is clarified that protonation-deprotonation of $\alpha$-amino group gives marked influence on the rate and selectivity of the photocatalytic reaction. On the basis of these results, it is concluded that the selective production of optically pure L-PCA, especially in an acidic suspension of TiO$_2$-Pt, was attributed to the enhanced protonation of $\alpha$-amino group to prevent undesirable oxidation by photogenerated positive holes and blocking of $\varepsilon$-amino group to yield racemic Schiff base intermediate.

• International Journal of Human Ecology
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• 제8권1호
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• pp.53-66
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• 2007

The purpose of the study is to microscopically re-clarify the reality of renovation and conflicts that females faced within their families since the modernization period. The research method is the literature review. Families have been considered based on the formation of individual spaces for housing by husband and wife. The study will analyze changes in daily lives and housing consciousness to understand how such housing areas are transforming. The results of the study are as follows. From the perspective of symbolic interaction, in a traditional society, Korean females have been experiencing alienation and isolation in private areas in their daily lives due to family centrism and male chauvinism. Since industrialization, the female's role as the major consumer has been emphasized. Also, in terms of housing space, the symbol of family interaction was influenced more by utility, rationality, and equality than spatial hierarchy. From the perspective of the dailiness of phenomenological traditions, the modern girl's housing consciousness, which appeared during modernization under colonial rule, is considered as revolutionary from traditional society. Soon after in industrialized society, females appeared as leaders of 'sweet home'. They also became the main body to create the space for living by giving meaning to the interior of housing. Considering dailiness from the Marxist perspective, under the colonial social system, females became the subject of colonization through education, socialization, and the labor market. The modern public system presents the female as 'a wise mom and good wife' or laborer causing the colonization of her life. After industrialization, the socialization of housing and prioritization of spending caused the daily lives of females to become colonized by the consumption market.

• Tuberculosis and Respiratory Diseases
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• 제51권1호
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• pp.70-75
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• 2001

저자들은 폐결핵의 병력이 있던 2명의 환자에서 기침과 객담을 주소로 내원하여 단순 흉부 방사선과 흉부 전산화 단층 촬영 결과 흉막비후와 기관지흉막루를 의심할 수 있는 공동형성을 보이고 흉막 천자액 배양과 수술후 조직배양검사결과 Aspergillus fumi-gatus가 확인되어 수술 및 항진균제를 사용하여 치료한 2례를 경험하였기에 이를 보고하는 바이다.