• Title/Summary/Keyword: columnar type

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A Study on the Fabrication and Structural Evaluation of AlN Thin Films

  • Han, Seung-Oh;Han, Chang-Suk
    • Journal of the Korean Society for Heat Treatment
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    • v.23 no.2
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    • pp.69-74
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    • 2010
  • AlN thin films were deposited by using a two-facing-targets type sputtering system (TFTS), and their deposition characteristics, microstructure and texture were investigated. Total gas pressure was kept constant at 0.4 Pa and the partial pressures of nitrogen, $PN_2$ (($N_2$ pressure)/($Ar+N_2$ pressure)) varied from 0 to 0.4 Pa. The texture of the film cross-sections and surface morphology were observed by field emission scanning electron microscope (FE-SEM). The crystallographic orientation of the films were analyzed by X-ray diffraction (XRD). Deposition of AlN film depends on $N_2$ partial pressure. The best preferred oriented AlN thin films can be deposited at a nitrogen partial pressure of $PN_2$ = 0.52. As-deposited AlN films show preferred orientation and columnar structure, and the grAlN size of AlN films increases with increasing sputtering current.

Thin film characteristics variation of static deposition and dynamic deposition by bipolar pulsed DC magnetron sputtering (Bipolar pulsed DC magnetron sputtering에서 정적 증착과 동적 증착에 의한 박막 특성 변화)

  • Yang, Won-Gyun;Ju, Jeong-Hun
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2009.05a
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    • pp.149-149
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    • 2009
  • 실제 산업에서 가장 많이 사용하고 있는 in-line type system에서 Al-doped ZnO (AZO) 막을 bipolar pulsed DC sputtering을 이용해 증착하였다. 약 30 nm/sec의 속도로 기판을 타겟 좌우로 swing 하면서 동적 증착 공정을 한 AZO 박막의 columnar structure가 정적 증착일 때와 다른 형태의 zigzag-type columnar structure가 형성되었다. 투명전도막의 가장 중요한 특성인 비저항과 투과도가 동적 증착 공정일 때의 박막과 정적 증착 공정일 때의 박막이 각각 $2.5{\times}10^{-3}{\Omega}{\cdot}cm$, 78.5%와 $1.65{\times}10^{-3}{\Omega}{\cdot}cm$, 83.9% 였다. 이렇게 성장하는 막의 구조 형태에 따라 달라지는 특성 변화는 양산하는 현장에서 매우 중요한 것이며, 동적 증착 공정에서의 박막 특성 개선에 정적 증착 공정과는 다른 방법의 연구가 필요할 것이다.

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Histological and Histochemical Studies on the Epididymal Region and Deferent Ducts of the Drakes by the Age in Weeks (오리 부고환(副睾丸) 및 정관(精管)의 주령별(週齡別) 조직학적(組織學的) 및 조직화학적(組織化學的) 연구(硏究))

  • Lee, Jae-Hong;Ha, Chang-Su
    • Korean Journal of Veterinary Research
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    • v.23 no.2
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    • pp.137-148
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    • 1983
  • This study was made for the better information of the male reproductive system on the meat-type drake, Cherry Belly X White Golden. The epithelium of ductules of epididymal region and deferent duct were observed histologically and histochemically with the progress of their development. India-ink absorbability on the luminal epithelium was also investigated after the administration of India-ink. The results are as follows; 1. Rete testis and various round ductules in immature form appeared in epididymis within 6 weeks after hatching, and simple cuboidal and simple columnar epithelium were found in the epithelia of the ductules within 8 weeks after hatching. Larger ductules were found on epididymal surface which was in the developing stage near to the immature efferent ductule. From 10th to 20th week, various ductules appeared in epididymis, and developing form of efferent ductules were much more increased on epididymal surface. The luminal epithelium of the ductules were composed of ciliated simple columnar and pseudostratified ciliated columnar cells. At the same time, deferent duct appeared. From the 21th week, various ductules in epididymis became abruptly matured. Lumen of rete testis was lined by simple squamous or simple cuboidal epithelium, and that of efferent ductules, having many folds and being larger than any others were lined by pseudostratified ciliated columnar epithelium in which ciliated columnar cells, non-ciliated cells(clear cells) and basal cells were noted. Connecting tubules of star shaped lumen were composed of pseudostratified ciliated columnar epithelium in which ciliated columnar cells, nonciliated cells, and basal cells were observed. The luminal surface of epididymal ducts was smooth and has thick pseudostratified columnar epithelium which was composed of high columnar cells and basal cells. From 26th week after hatching, sperm pooling was started in various ductules. 2. From 4th to 10th week, simple cuboidal epithelium of deferent duct transformed to simple columnar epithelium with the progress of aging. At the basement of epithelium, clear round cells were noted. From 12th to 20th week, high columnar cells with enlongated nucleus were noted on the luminal border of deferent ducts, forming folds of pseuclostratified columnar epithelium. From 20th week, the deferent duct started to have septa in it's lumen and composed mainly of pseudostratified columnar epithelium, and round cells disappeared. From 20th week, the lumen diameter of deferent duct became wider with the progress of aging, but there was no difference among the values of lumen diameter in upper, middle, and lower part of deferent ducts. At 26th week, the pooling period of sperms in deferent ducts, the lumen diameter became rapidly widen, especially in the lower part of deferent ducts. Thickness of muscular layer of ductus deferens showed gradual growth within 24 weeks but did abrupt thickening from 26th week. 3. Saliva resistant PAS granules were dotted on the top of nucleus in efferent ductules epithelium but the amount of the granules were little in the connecting ductules's epithelium. The granules reactive to acid phosphatase were abundant in the some epithelial cells of efferent ductules and connecting ductules, especially above the nucleus of cells. The granules reactive to alkaline phosphatase were noted on the luminal border of efferent ductules. Parts of free border of efferent ductules and middle portion of deferent ducts were stained slightly by alcian blue technique. India ink granules were found mainly in the epithelium of efferent ductules but were few in that of connecting ductules.

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감귤저장시 부패균 증식억제를 위한 식물유래 천연항균제 탐색

  • Ha, Cheol-Gyu;Lee, Dong-Gyu;Gang, Seon-Cheol
    • 한국생물공학회:학술대회논문집
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    • 2000.04a
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    • pp.453-456
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    • 2000
  • Antifungal activities of domestic plants were examined to develope natural antimicrobial agents, able to protect citrus fruits from spoiling microorganism during their storage. A fungus was isolated from citrus fruits' storage and identified to Penicillium sp. CF-301, based on the morphological characteristics of conidiophore and conidia; flask shape of phialide, simple branching type of conidiophore, and columnar shape of conidial head, in malt extract agar and potato dextrose agar media. Chloroform extracts of Juniperus chinesis Linnaeus, J. chinesis var. horizontalis showed remarkable antifungal activities against Penicillium sp. CF-301.

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Microstructures and Textures of Electrodeposited Ni/Invar Bimetal (전주도금으로 제조된 Ni/Invar 바이메탈의 미세조직과 집합조직)

  • Kang, Ji Hoon;Seo, Jeong Ho;Park, Yong Bum
    • Korean Journal of Metals and Materials
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    • v.46 no.7
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    • pp.420-426
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    • 2008
  • By using electrodeposition, we developed a new method to produce Ni/Invar bimetal sheets, which have been used for the present study to investigate the texture evolution during annealing. The grains of electrodeposited Ni were columnar, while those of electrodeposited Fe-Ni alloy were nanocrystalline. These different parts of the bimetal underwent different evolution of textures and microstructures during annealing. In the nanocrystalline Invar, the as-deposited textures were of fiber-type characterized by strong <100>//ND and weak <111>//ND components, and the occurrence of grain growth resulted in the strong development of the <111>//ND fiber texture with the minor <100> // ND components. On the other hand, in the columnar-structured Ni part, the as-deposited <110>//ND fiber texture transformed to the <112>//ND fiber texture due to recrystallization occurring above $550^{\circ}C$. The development of microtextures which took place during annealing in the Ni/Invar interfacial regions was investigated by using the OIM analysis, and discussed in terms of the effect of atomic diffusion across the interfaces.

Primary Non-clear-cell Adenocarcinoma of the Vagina -Report of a Case- (질에 발생한 원발성 비투명세포선암 -1예 보고-)

  • Jee, M.K.;Choi, Y.I.;Yang, K.W.;Kim, B.K.;Kim, S.M.
    • The Korean Journal of Cytopathology
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    • v.1 no.1
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    • pp.103-110
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    • 1990
  • A case of primary non-clear-cell adenocarcinoma of the vagina is reported occurring in a 65-year-old woman without exposure to diethylstilbestrol (DES) in utero. The adenocarcinoma did not appear to be associated with vaginal adenosis. It lacked clear cell component and interestingly composed of columnar epithelial cells of endocervical-type. Cytologically round to oval nuclei revealed one or more small nucleoli and fine granular chromatin pattern. Cytoplasm was plump, faintly basophilic and homogeneously stained. Histologically well differentiated columnar epithelial cells were arranged on trabecular pattern mainly, and also occasional glandular lumina and small solid sheets were found. Mitoses were hardly found.

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Mechanical Properties of Unidirectional Carbon-carbon Composites as a Function of Fiber Volume Content

  • Dhakate, S.R.;Mathur, R.B.;Dham, T.L.
    • Carbon letters
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    • v.3 no.3
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    • pp.127-132
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    • 2002
  • Unidirectional polymer composites were prepared using high-strength carbon fibers as reinforcement and phenolic resin as matrix precursor with keeping fiber volume fraction at 30, 40, 50 and 60% respectively. These composites were carbonized at $1000^{\circ}C$ and graphitised at $2600^{\circ}C$ in the inert atmosphere. The carbonized and graphitised composites were characterized for mechanical properties as well as microstructure. Microscopic studies were carried out of the polished surface of carbonized and graphitised composites after etching by chromic acid, to understand the effect of fiber volume fraction on oxidation at fiber-matrix interface. It is found that the flexural strength in polymer composites increases with fiber volume fraction and so does for the carbonised composites. However, the trend was found to be reversed in graphitised composites. In all the carbonized composites anisotropic region has been observed at fiber-matrix interface which transforms into columnar type microstructure upon graphitisation. The extension of strong and weak columnar type microstructure is function of fiber volume fraction. SEM microscopy of the etched surface of the sample reveal that composites containing 40% fiber volume has minimum oxidation at the interface, revealing a strong interfacial bonding.

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New Columnar Apple Variety 'Tinkerbell' for Pollenizer (사과 무측지성 수분수용 신품종 '팅커벨')

  • Kwon, Soon-Il;Kwon, Young Soon;Park, Jong-Taek;Kim, Mok-Jong;Kim, Jeong-Hee
    • Journal of Bio-Environment Control
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    • v.25 no.3
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    • pp.173-176
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    • 2016
  • This research was performed to breed new columnar-typed apple variety for pollinator in apple orchard. We cross-fertilized 'Hongro' that was an ovary parent and 'Maypole' a pollen parent in 2003. We gathered seeds in 2003 and sowed after breaking of dormancy in 2004. Seedlings was been growth and development till flowering. After fruit setting, We investigated characteristics of growth and fruit including mating compatibility from 2010 to 2012, then finally selected '03-2-95' named 'Tinkerbell' in 2012, registered as new variety on Korea Seed & Variety Service in 2015. The full bloom stage of 'Tinkerbell' was later 2 days then of 'Maypole'. Tree habit of 'Tinkerbell' was alike to of 'Maypole', for example weak tree vigor, columnar type. But there were many different characteristics between 'Tinkerbell' and 'Maypole'. Fruit shape of 'Tinkerbell' was ovoid whereas of 'Maypole' was ellipsoid. Fruit of 'Tinkerbell' was bigger, smoother skin, no waxy bloom than of 'Maypole'. Fruit of 'Tinkerbell' was more delicious than of 'Maypole' because of having higher soluble sugar content and lower titratable acidity. 'Tinkerbell' was excellent pollinator in apple orchard. Because of having high fruit setting rate with major apple varieties and a narrow tree width that was advantageous as pollinator in apple high density system.

Study of the Method to Examine the Cause of Damage to a Flat-Type Vinyl Cord (VFF) According to the Type of Energy Source (에너지원의 종류에 따른 비닐평형코드(VFF)의 소손원인 판정기법에 관한 연구)

  • Choi, Chung-Seog
    • Fire Science and Engineering
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    • v.25 no.6
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    • pp.83-88
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    • 2011
  • This study presented the structure and characteristics of vinyl cords used for wiring electric equipment and appliances and analyzed the photographs of damaged flat-type vinyl cords (VFF, $1.25mm^2$) and the metallic cross-sectional structure of melted conductors. Normal VFFs were made by twisting several strands together and the surface of the conductor was red brown. In addition, from the analysis of the metallic structure of the conductor, it was found that its grains had been elongated. The surface of a VFF damaged by normal flame showed no sheen with carbonized insulation material fused on the conductor surface. In addition, from the analysis of the cross-sectional structure of the melted area, it was found that voids of a certain shape were formed on it but that the cord's own elongation structure could not be checked. The cross-sectional analysis of the melted conductor damaged by the external flame applied to a VFF to which electric current was being applied showed no elongation structure for each cord, and revealed that irregular voids and a columnar structure had grown. The surface of the VFF damaged by overcurrent was uniformly carbonized and the cross-sectional structure analysis of the melted conductor revealed that the dendritic structure had grown. The analysis of the characteristics of the VFF melted by short-circuit showed that even though some part of the surface was contaminated, it showed little sheen and that the area rebounded by melting was round in shape. In addition, the cross-sectional structure analysis using a metallurgical microscope showed the boundary surface and columnar structure and revealed an amorphous structure like normal copper at areas other than the melted conductor.

A Study on Evaluation of Slope Stability and Range of Rockfall Hazard of Daljeon-ri Columnar Joint in Pohang, Korea (천연기념물 제415호 포항 달전리 주상절리의 사면안정성 평가 및 낙석 위험 범위 설정)

  • Kim, Jae Hwan;Kang, Mu Hwan;Kong, Dal-Yong;Jwa, Yong-Joo
    • Journal of Conservation Science
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    • v.37 no.5
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    • pp.505-515
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    • 2021
  • In this study, we evaluated the slope stability of the Pohang Daljeon-ri columnar joint (Natural Monuments # 415) and calculated the maximum energy, jumping height and moving distance of rockfalls using a simulation. Based on the results, we established the range of rockfall risk. The slopes of the Pohang Daljeon-ri columnar joint have dip directions of 93.79°, 131.99°, 165.54° and 259.84° from left (SW) to right (NE). Furthermore, they have a fan-like shape. The Pohang Daljeon-ri columnar joints are divided into four sections depending on the dip direction. The measurement results of the discontinuous face show that zone 1 is 125, zone 2 is 261, zone 3 is 262, zone 4 is 43. The results of slope stability analyses for each section using a stereographic projection method correspond to the range of planar and toppling failure. Although it is difficult to diagnose the type of failure, risk evaluation of currently falling rocks requires further focus. The maximum movement distance of a rockfall in the simulation was approximately 66 m and the rockfall risk range was the entire area under slope. In addition, it is difficult to forecast where a rock will fall as it rolls in various directions due to topographic factors. Thus, the installation of measures to prevent falling is suggested to secure the stability based on the results of the rockfall simulations and its probabilistic analysis.