• Title/Summary/Keyword: Crest flat

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Hydrophillic and Hydrophobic Properties of Sol-Gel Processed Sillica Coating Layers

  • Kim, Eun-Kyeong;Lee, Chul-Sung;Hwang, Tae-Jin;Kim, Sang-Sub
    • Proceedings of the Korean Vacuum Society Conference
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    • 2011.02a
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    • pp.505-505
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    • 2011
  • The control of wettability of thin films is of great importance and its success surely brings us huge applications such as self-cleaning, antifogging and bio-passive treatments. Usually, the control is accomplished by modifying either surface energy or surface topography of films. In general, hydrophobic surface can be produced by coating low surface energy materials such as fluoropolymer or by increasing surface roughness. In contrast, to enhance the hydrophillicity of solid surfaces, high surface energy and smoothness are required. Silica (SiO2) is environmentally safe, harmless to human body and excellently inert to most chemicals. Also its chemical composition is made up of the most abundant elements on the earth's crest, which means that SiO2 is inherently economical in synthesis. Moreover, modification in chemistry of SiO2 into various inorganic-organic hybrid materials and synthesis of films are easily undertaken with the sol-gel process. The contact angle of water on a flat silica surface on which the Young's equation operates shows ~50o. This is a slightly hydrophilic surface. Many attempts have been made to enhance hydrophilicity of silica surfaces. In recent years, superhydrophilic and antireflective coatings of silica were fabricated from silica nanoparticles and polyelectrolytes via a layer-by-layer assembly and postcalcination treatment. This coating layer has a high transmittance value of 97.1% and a short water spread time to flat of <0.5 s, indicating that both antireflective and superhydrophilic functions were realized on the silica surfaces. In this study, we assessed hydrophillicity and hydrophobicity of silica coating layers that were synthesized using the sol-gel process. Systematic changes of processing parameters greatly influence their surface properties.

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Morphological classification of the moderator band and its relationship with the anterior papillary muscle

  • Lee, Ju-Young;Hur, Mi-Sun
    • Anatomy and Cell Biology
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    • v.52 no.1
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    • pp.38-42
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    • 2019
  • This study investigated and classified the various types of moderator band (MB) in relation to the anterior papillary muscle, with the aim of providing anatomical reference information and fundamental knowledge for use when repairing the congenital defects and understanding the conduction system. The study investigated 38 formalin-fixed human hearts of both sexes obtained from donors aged 38-90 years. The MB was evident in 36 of the 38 specimens (94.7%). The morphology of the MB and its connection with the APM took various forms. The MBs that had a distinct shape were classified into three types according to their shape: cylindrical column, long and thin column, and wide and flat column. Types 2 and 3 were the most common, appearing in 15 (41.7%) and 14 (38.9%) of the 36 specimens, respectively, while type 1 was observed in seven specimens (19.4%). Type 3 was divided into subtypes based on their length. The MB usually originated from a single root (91.7%), with the remainder exhibiting double roots. The pairs of roots in the latter cases had different shapes. The originating point of the MB ranged from the supraventricular crest to the apex of the ventricle. The most-common originating point was in the middle (25 of 36 specimens, 69.4%), followed by the upper third (13.9%), the lower third (11.1%), and the top fifth (5.6%) of the interventricular septum. This study has produced fundamental anatomical and clinical information that will be useful when designing cardiac surgical procedures.

Analysis of the Geomorphological Environments of High-Density Residential Zone in Bronze Age around Asan City, Central Korea - A Case Study of Yongdoocheon and Onyangcheon Basin - (충남 아산의 청동기 시대 주거지 밀집 구역의 지형환경 분석 - 용두천과 온양천 유역을 사례로 -)

  • Park, Ji-Hoon;Park, Jong-Chul
    • Journal of the Korean Association of Geographic Information Studies
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    • v.14 no.3
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    • pp.110-125
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    • 2011
  • A number of the Bronze Age dwelling sites have been found and excavated in the Yoodoocheon, Onyangcheon and Baekseokdong basins. Two basins are located near Asan and Onyan in the Chungnam Province of South Korea. Baekseokdong is located in Cheonan, Chungnam. 207 dwelling sites are concentrated around the area of $1.3km^2$ in the Baekseokdong. 177 dwelling sites are sparse and distributed over the area of $1.3km^2$ in the Yongdoocheon and Onyangcheon basins. Most of the Bronze Age dwelling sites in those areas located on the hill. The hills have similar geomorphological environments except for slight differences in geological faces. This study analyzes geomorphological environments of the high-density residential zone of the Bronze Age in the Yoodoocheon and the Onyangcheon basins, and then compares them with the results in Baekseokdong. Study results show that high-density residential zone consists mainly of specific micro-landforms such as the Crest slope, the Crest flat and the Upper side slope, and southeast-facing aspect. A lot of Gentle slope lands were distributed in terms of terrain slope but it is far from specific geomorphological environments. This is not weighted in specific value. Our results show that the geomorphological characteristic derived from this study is major considerations to develop dwelling sites in the Bronze Age. This can be useful to discover the possible dwelling sites over other Chungnam hill regions.

First Record of the Cutlass Fishes, Benthodesmus tenuis (Perciformes: Trichiuridae) from Korea (한국산 갈치과 어류 1 미기록종, Benthodesmus tenuis)

  • Kim, Maeng Jin;Choi, Jung Hwa;Oh, Tag Yun;Kim, Jung Yun;Lee, Dong Woo
    • Korean Journal of Ichthyology
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    • v.24 no.4
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    • pp.302-305
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    • 2012
  • Two specimens (332.0~377.6 mm in standard length) of Benthodesmus tenuis (G$\ddot{u}$nther), belonging to the family Trichiuridae, firstly collected in off Heuksan-do and Yeosu, Jeollanam-do by the bottom trawl. This species was characterized by the following morphological traits: 125~126 dorsal fin rays (vs. 144~155 for B. pacificus), I, 73 anal fin rays (vs. 91~101), interorbital region flat (vs. interorbital region with prominent crest for A. anzac), opercular black and caudal fin forked. We propose a new Korean name, "Se-jang-gal-chi-sok" and "Se-jang-gal-chi" for the genus and species, respectively.