• Title/Summary/Keyword: 수성들

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Fabrication of Super-hydrophobic Surface using Solubility Difference of Polystyrene at Two Different Solvents (두 용매에서의 폴리스타이렌의 용해도 차이를 이용한 초소수성 표면 제조)

  • Jung, Jin-Suk;Park, Kwang-Bae;Choi, Ho-Suk
    • Clean Technology
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    • v.14 no.1
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    • pp.35-39
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    • 2008
  • In this study, we successfully fabricated a super-hydrophobic polymer layer on the surface of slide glass using the solubility difference of a polymer at two different solvents. After dissolving polystyrene (PS) resins in tetrahydrofuran (THF) as a good solvent and then adding ethanol(EtOH) as a poor solvent, we were able to fabricate super-hydrophobic surface. We also investigated the effect of EtOH addition, coating methods, solution mixing time and speed, and other alcohols on the surface hydrophobicity. The water contact angle (WCA) of the fabricated surface revealed $WCA>150^{\circ}$ and the microporous surface structure composed of microparticles with the size less than $5\;{\mu}m$.

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Applying Aqueous Two Phase Systems to Multi-layer Cosmetics (다중 층 화장료에서 수성 이상계의 응용)

  • Hong, Junki;You, Jaewon;Yoo, Jangyung;Nam, Seungok;Lee, Sanggil;Pyo, Hyeongbae
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.39 no.2
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    • pp.83-88
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    • 2013
  • The aqueous two phase system has biocompatibility, because it is physically separated into an immiscible liquid multi-layer induced by incompatibility among hydrophilic components dissolved in the water phase. we have applied this principle to aqueous multi-layer liquid cosmetics and select two representative systems. What it was experimentally obtained was the phase diagrams including a binodal curve, a critical point, tie lines of concentration and tie curves of phase separating volume ratio and phase separating time. From the phase diagrams, we were able to observe existence of the optimum condition to prepare the aqueous multi-layer cosmetics for the systems.

A Study on Origins of the Geographical Name in Daegu Metropolitan Area : Based on the Geographical Name of Dong(洞) (대구 지명유래에 관한 연구 - '동(洞)명'을 사례로 -)

  • Jeon, Young-Gweon
    • Journal of the Korean association of regional geographers
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    • v.19 no.3
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    • pp.375-383
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    • 2013
  • The main results that can be drawn from the thematical analysis, based on 173 geographical names of Dong(洞) in Daegu city, are as follows. Firstly, the origin of the geographical name of Dong is divided into 10 groups such as natural landscape, human landscape, situation, and so on. Thematically, natural landscape is the most important factor among them. In particular, Dong-gu is such a case since Mt. Palgong and Geumho river are widely distributed around the area. Secondly, the origins of the geographical name of Dong in Jung-gu and Buk-gu are mainly concerned with human landscape and situation. Especially, Daegu-Eupseong(大邱邑城) has a great influence on the origin of the geographical name of Dong in Jung-gu. Thirdly, in 1914, the unification of administrative district established new Dongs(洞) and the geographical names of the new Dongs were made by borrowing each word from the existing geographical names of Dong. Fourthly, the geographical names of Dong in Suseong-gu and Dalseo-gu made after 1980s' were made in many cases by utilizing the existing natural landscapes. However, it is identified that Suseong field in Suseong-gu, Seongdang lake and Mt. waryong in Dalseo-gu have been recognized as the important natural landscapes. Lastly, the geographical name of Dong is commonly concerned with historical place names such as Gongsan battle in Dong-gu. It is judged that the geographical names of Dong based on Gongsan battle or a most intriguing piece of legend will make a great contribution on developing the regional tourism by storytelling.

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Effeets of Environmental pH on the Heat Shoek Proteins and Thermosensitivity of Mouse Fibroblasts and SCK Tumor Cells* (생쥐의 섬유아세포와 SCK 종양세포의 Heat Shock Protein과 열감수성에 미치는 pH의 영향)

  • 강만식;이정주서미영고득수
    • The Korean Journal of Zoology
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    • v.30 no.3
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    • pp.311-323
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    • 1987
  • 생쥐의 섬 유아세포(MEP)와 종양세포(SCK)를 이용하여 정상세포와 종양세포 사이에 열 감수성의 차이가 있는지의 여부 및 환경의 pH가 이 세포들의 열감수성과 heat shock protein(HSP) 합성에 미치는 영향을 생존곡선과 HSP합성 kinetics등을 써서 검토하였다. MEF와 SCK 세포를 정상 pH(7.4) 또는 산성 pH(6.7)에서 42"C에서 2시간 온열처리 후 3일간에 걸쳐 생존을을 비교해 븐 결과, ME선와 SCK세포 사이에 생득적 열강수성의 차이는 없었고 산성 P광에서는 세포의 종류에 관계없이 열감수성 이 증감되었다. 온열처리의 결과 유도되는 내일성이 conditioning Leat의 크기와 어떤 관계가 있는지를 보기 위해서 45"C에서 5분 또는 20분을 주어본 결과 체은 conditioning heat를 주었을 때 내일성이 신속히 그리고 높은 수준으로 발생하였고, 이러한 열 감수성의 kinetics는 HSP의 합성 kinetics와 잘 일치하였다. 단백질, 특히 HSP 합성에 미치는 PH의 영 향을 알아보기 위해서 46"C에서 6분간의 heat shock를 주어 본 바 전반적인 단백질 및 major HSP의 합성양상에는 별로 차이를 보이지 않았다. 그러나 SCK 세포에 43"C에서 30분의 온열처리를 주고 새로 합성되는 HSPSP의 kinetics를 검토해 본 결과 정상 P반에서는 0-5시간에 합성이 일어나나 산성 PH에서는 3-9시간에 합성이 일어나서 몇시간의 합성지연이 관찰되었다. 아울러 HSP68, HSPTC, HSP87을 Peptidemapping하여 본 결과 HSP68과 HSP70 은 유사한 peptide fragment pattern을 보여 amino acid sequence는 유사하고 기능도 같을 것으로 추론되었으나 HSP87은 전혀 다른 pattern을 보였다. 전혀 다른 pattern을 보였다.

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Crystal Structure and Superhydrophilic Property of $TiO_2$ Thin Film Coated on Si(100) Wafer (Si(100) 기판 위에 코팅된 $TiO_2$박막의 결정구조와 초친수 특성)

  • 김사라;조운조;박재관;이용철
    • Korean Journal of Crystallography
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    • v.12 no.3
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    • pp.177-181
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    • 2001
  • We have studied superhydrophilic properties of TiO₂thin films in relation with those crystal structures due to the heat treatments. Thin films were fabricated on Si (100) wafers using a conventional Sol-Gel method. Following drying and sintering processes, TiO₂film had an anatase phase with additional heat treatment at 500℃, an rutile phase at 1000℃, and a mixture of anatase and rutile phase at 750℃. All these films got hydrophilic even without any UV illumination. Especially the sample treated at 750℃ had a superhydrophilic contact angle of 5°. We suggested that the superhydrophilic films should have a mixture of anatase and rutile phase for the best performance. The hydrophilic TiO₂films were slowly degraded into the hydrophobic state in the dark room but quickly recovered back with les than 1 hour of UV illumination.

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Varietal Differences of Germinative Traits Related with Malting Barley Breeding (맥관맥의 발아관련형질들의 품종간 차이)

  • Nam, Jung-Hyun;Lee, Eun-Sup;Park, Moon-Woong
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.31 no.3
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    • pp.350-355
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    • 1986
  • Sixteen Korean leading barley varieties were tested on the sixtieth day after harvest, in order to investigate differences for germinative traits related, and on the eightieth day to test optimum water level for germination test. The germinative energy(GE) and capacity(GC) in the 4.5cc water level were the highest individually. Varietal variations among GE, GC, promptness index(PI) and water sensitivity(WS) were highly significant in storage conditions and water levels. Correlation coefficient estimated were positive among GE, GC, PI, but negative between these traits and WS. Also the varietal difference of WS gets higher with the following order of malting barley<naked barley<covered barley. Heritabilities of broad sense for GE, GC, PI and WS were high, therefore, these traits could be considered in malting barley breeding.

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An Analysis on the Determining Factors of Satisfaction for Environmental Improvement of Trails around Recreation Park - Focused on Suseong Recreation Park in Daegu - (유원지 주변 산책로의 환경개선을 위한 이용만족도 결정요인 분석 - 대구광역시 수성유원지를 대상으로 -)

  • Kim, Dong-Seok;Lee, Woo-Sung;Jung, Sung-Gwan
    • Journal of the Korean Institute of Landscape Architecture
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    • v.43 no.5
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    • pp.28-39
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    • 2015
  • The purpose of this study is to analyze users' behavior and facility satisfaction and to suggest the practical solution plans for environmental improvement of trails in Suseong recreation park in Daegu. Therefore, satisfaction factor analysis on trails was carried out based on a field and questionnaire survey in Suseong recreation park. First, from users' behavior, 48% of users visited Suseong recreation park for walking. The greatest response to number of visits was once or twice a week, and average use time per visit was 80.4 minutes. In terms of trails, the greater responses to the number of visits were once(38.1%) or more than 5 times(23.8%), and average use time was 45.4 minutes. According to the results from the analysis of facility satisfaction, management condition, length, slope, and adjacent natural landscape of trails were evaluated at a satisfaction rate higher than 3.4 points. However, water pollution, and number of exits and parking lots were analyzed at a low rate of 2.75 and 2.78 points, respectively. In terms of analyzing determining factors of facility satisfaction for trails, use of facilities, walking convenience, surrounding landscapes, amenities, and noise had a significantly positive effect on satisfaction. In particular, walking convenience was the highest effect factor; its standardized coefficient was 0.533. The findings from this study can contribute to the improvement of the physical environment for trails of Suseong recreation park and provide basic data for plan and maintenance of similar waterside trails.

Characteristics of Water Gas Shift and Membrane Process for Pre-combustion CO2 Capture (연소전 CO2 포집을 위한 수성가스반응과 분리막 공정 특성)

  • Kim, Jeong-Nam;You, Jong-Kyun;Choi, Soo-Hyun;Baek, Il-Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.17 no.1
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    • pp.21-27
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    • 2016
  • Global warming due to greenhouse gas emissions is considered as a major problem worldwide, and many countries are making great efforts to reduce carbon dioxide emissions. Many technologies in post-combustion, pre-combustion and oxy-fuel combustion $CO_2$ capture have been developed. Among them, a hybrid pre-combustion $CO_2$ capture system of a water gas shift (WGS) reactor and a membrane gas separation unit was investigated. The 2 stage WGS reactor integrated high temperature shift (HTS) with a low temperature shift (LTS) was used to obtain a higher CO conversion rate. A Pd/Cu dense metal membrane was used to separate $H_2$ from $CO_2$ selectively. The performance of the hybrid system in terms of CO conversion and $H_2$ separation was evaluated using a 65% CO, 30 % $H_2$ and 5% $CO_2$ gas mixture for applications to pre-combustion $CO_2$ capture. The experiments were carried out over the range of WGS temperatures ($200-400^{\circ}C$), WGS pressures (0-20bar), Steam/Carbon (S/C) ratios (2.5-5) in a feed gas flow rate of 1 L/min. A very high CO conversion rate of 99.5% was achieved with the HTS-LTS 2 stage water gas shift reactor, and 83% $CO_2$ was concentrated in the retentate using the Pd/Cu membrane.

Development indices for the Waterfront Creation (수변공간조성을 위한 지표 개발)

  • Park, Ki Bum;Ahn, Seung Seop;Moon, Sang Chul;Park, So Yun
    • Proceedings of the Korea Water Resources Association Conference
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    • 2016.05a
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    • pp.506-506
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    • 2016
  • 수변공간을 개발하는 방향에 있어서 홍수에 안전하고 수자원의 이용기술이 발달하면서 수자원 안전성이 크게 향상되어 수변공간개발은 이용성을 증가시키는 방향으로 진행되고 있다. 대표적인 수변공간 개발인 청계천은 이제 많은 사람들이 방문하고 여가를 즐기고 휴식을 취하는 공간으로 전국적으로 유명한 관광명소가 되었다. 청계천과 같이 유명한 수변공간이 아니더라도 지역의 주거지와 가까운 곳에 하천과 수변공간들이 이미 많은 사람들이 운동, 산책, 휴식, 여가활동을 즐기는 공간으로 인간에게 다가오고 있다. 이러한 수변공간을 개발하는 데 있어 지금까지 개발의 방향을 결정하는 주체는 지자체의 담당공무원과 기술자들에 의해 개발의 방향이 결정되어 왔다. 최근들어 이수와 치수에 있어 안정성이 과거보다 크게 상향되면서 하천은 인간에게 친숙한 공간이 되고 있다. 시대의 흐름이 수변공간의 활용이 높아지고 과거와 달리 홍수방어나 수자원을 공급하는 자연 시설이 아닌 인간이 다양한 목적으로 이용이 가능한 공간으로 변해가고 있다. 이러한 공간을 개발하는데 있어 지형적, 사회문화적 특성을 반영시키고 이용도를 증진시키기 위해 이용자들의 성향을 파악하고 객관적인 지표를 개발할 필요가 있다. 본 연구에서는 대구에 위치한 대표적인 수변공간인 수성못과 신천 그리고 팔거천을 대상으로 이용자들의 설문조사를 실시하고 그 결과를 이용하여 수변공간을 개발하는 데 있어 정량적인 지표들을 제시하고자 한다.

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Osteolysis-Related Bioabsorbable Suture Anchor Fixation in a Medial Collateral Ligament Avulsion Fracture during Total Knee Arthroplasty (슬관절 인공관절 치환술 중 발생한 내측 측부 인대 견열 골절에 대해 생흡수성 봉합 나사못을 이용한 고정 후 발생한 골용해)

  • Huh, Jung-Wook;Park, Man-Jun;Hong, Seong-Hwak;Park, Joon-Hyung
    • Journal of the Korean Orthopaedic Association
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    • v.55 no.6
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    • pp.545-549
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    • 2020
  • Although rare, the treatment options for a medial collateral avulsion fracture during total knee arthroplasty (TKA) range from conservative management using a cast and orthosis to internal fixation using metal screws. Bioabsorbable suture anchors have been used to replace metal fixators with distinct advantages, such as biocompatibility, radiolucency, and unnecessary second removal surgery, but complications, such as osteolysis, have been reported. This paper reports a potential risk of an extensive osteolysis-related suture anchor fixation of a medial collateral ligament (MCL) avulsion fracture during TKA in conjunction with a literature review.