• Journal of the Korean Society of Propulsion Engineers
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• v.23 no.2
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• pp.46-52
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• 2019

This research was conducted to analyze the effects of temperature on coking characteristics of kerosene. The kerosene was heated to 600 K, 700 K, and 800 K, and the cooled samples were collected. The used copper tubes were replaced according to the temperature conditions. The liquid and copper specimens were analyzed by gas chromatography-mass spectrometry and scanning electron microscopy equipped with an energy dispersive x-ray spectrometer, respectively. The results of the analysis confirmed that a carbon deposit was formed from the coking of fuel on the inner surface of the copper specimen at a relatively high temperature (800 K) of the copper tube.

• Korean Journal of Veterinary Research
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• v.32 no.3
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• pp.381-387
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• 1992

Gill epithelia of normal rainbow trout fingerlings and abnormal ones suffering bacterial gill disease by experimental infection were examined by transmitting electron microscopy (TEM) and scanning electron microscopy (SEM). TEM observations revealed that Flavobacterium branchiophila consisted of slender rods measuring 0.5 by 5 to $8{\mu}m$, and they had which were long, thin, flexible filaments measuring approximately 4 nm by $1{\mu}m$, and packed together to organize into bundles. Morphological alterations of the diseased epithelia started at hypertrophy of the lamellar epithelium. F branchiophila attached to the gill surface of infected fish through pili with a regular distance, and did not invade into gill tissue. In SEM observations, normal surface ultrastructure of epithelial cell in the outermost layer were characterized by a typical labyrinth-like structure branching and anastomosing microridges on the cell surface. Hyperplastic lesions in experimentally infected gill were most serious at near the tips. Each filament exhibited a club-like, and fusion between the filaments was sometimes observed at their tips. On the surface of gill filaments, thread-like bacterial cells attached and were entangled. The bacterial cells almost covered the surface. After immersion in 5 % NaCl, the cell of F branchiophila, however, appeared to be indeterminate shape.

• Korean journal of applied entomology
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• v.29 no.3
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• pp.157-164
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• 1990

The surface patterns and the structures of transverse section of the egg-shell of the sikmoth, Bombyx mandarina, have been described by scanning electron microscope. Three spatially differentiated cross section, called lamellar, conic pillar and cover layers, are found on the mature eg-shell. Silkmoth chorion proteins were detected more than 80 components from a single chorion by two-dimensional electrophoresis. Major protein components of the egg-shell have bee identified on the basis of their isoelectric points and molecular weights, pH 4-6 and 6-30 kd. Several protein components are found entirely or predominantly in th cover layers.

• The korean journal of orthodontics
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• v.27 no.6 s.65
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• pp.979-995
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• 1997

The purpose of this study was to identify the preventive and the progressive inhibitory effects of enamel demineralization with fluoride releasing light-and self-cured orthodontic sealants(FluoroBond), in vitro, under the polarizing light microscope and the scanning electon microscope. The polarizing light microscopic group was subdivided into seven groups(Group A-Group G). The scanning electron microscopic group was also subdivided into seven groups(Group A'-Goup G'). For polarizing light microscopic evaluation, longitudinal sections were made longitudinally by Maruto cutter(Maruto Co., Japan) and Maruto grinding machine(Maruto Co., Japan). Sections were examined and photographed by the polarizing light microscope(Olympus Optical Co., Japan) using crossed polars and with the enamel rod longitudinal axis oriented at $45^{\circ}$ to the extinction position. For scanning electron microscopic evaluation, the specimens were coated with a highly conducting layer of gold palladium in a model Hus-4 high-vacuum evaporator and examined in an ISI-100B scanning electron microcope operated at 20kV. The results of this study were as follows : 1. The mean depths of artificial carious lesions under a polarized light microscope were $Group\;A(5.08{\mu}m),\;Group\;B(47.82{\mu}m,\;Group\;C(8.42{\mu}m),\;Group\;D(7.20{\mu}m),\;Group\;E(85.41{\mu}m),\;Group\;F(60.38{\mu}m),\;Group\;G(60.13{\mu}m)$. 2. There were statistically significant differences in Group B compared with Group A, C, and D(p<0.05), and also, in Group I compared with Group F and Group G(p<0.05). 3. Light-and self-cured orthodontic sealants had the preventive effects of enamel demineralization. 4. Light-and self-cured orthodontic sealants had the progressive inhibitory effects of enamel demineralization. 5. The time progress of demineralizing agent had no influence on the samples of light-and self-cured orthodontic sealants under the scanning electron microscope. 6. There was no difference between the specimens of light-and self-cured orthodontic sealants both in the polarized light microscopic group and in the scanning electron microscopic group.

• Journal of the Korean Vacuum Society
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• v.2 no.3
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• pp.374-383
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• 1993

필라멘트와 Si 기판 사이의 기전력을 20, 80, 140, 200V로 증가시키면서 EACVD에 의하여 성장된 다이아몬드 박막에 대하여 다이아몬드/Si 계면분석 및 계면강도를 측정하였다. 주사형전자현미경(SEM), 고분해능투과형전자현미경(HRTEM), 오제이전자분석기(AES)에 의해 계면상태를 분석한 결과, 기전력 증가에 따라 활성탄화수소 이온(CmHn-)에너지가 증가되어져 CmHn-이 Siso로 침투(Impringement)가 증가되고 침투된 높은 에너지의 CmHn-이 Si과 화학결합하여 생성되는 SiC층 깊이 및 농도 분포도 증가된다. 풀 시험(Pull test)에 의한 계면강도 측정 결과, SiC층 깊이 및 농도분포가 증가할수록 계면강도가 증가하였다. 관찰된 파면과 파면의 X-선 메핑 결과 및 HRTEM과 AES에 의한 분석 결과, 기전력 증가에 따라 공극율이 적고 치밀한 다이아몬드 박막이 성장된다. 그리고 생성되는 SiC층 농도 및 깊이 분포가 증가함에 따라 다이아몬드/Si 계면이 강화되고, 상대적으로 파괴는 다이아몬드/Si 계면이 아닌 SiC층이나 Si 내부에서 발생된다. 결국, 기전력을 증가하여 활성탄화수소이온의 에너지를 증가함으로써 계면강도가 우수하며 공극율이 매우 적고 치밀한 다이아몬드 박막을 성장할 수 있다.

• Journal of Korean Society of Forest Science
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• v.66 no.1
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• pp.64-67
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• 1984

The genus Salix is nowadays becoming increasingly important for both biomass energy production and the expanding paper industry. The enlarging plantations will however create some potential as well as problem. The great potential of genetical improvement as well as the prevention of pollen allergies requires knowledge about e.g, the pollen morphology of the most used Salix species. This study investigated the pollen morphology of Salix viminalis L. both on light microscope (LM) and scanning electron microscope (SEM).

• Journal of the Korean Society of Radiology
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• v.17 no.2
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• pp.223-230
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• 2023

This study attempted to concider the morphological change of red blood cells after whole body irradiation. Blood samples used red blood cells of white mice and mouse after irradiation. Transmission electron microscope observation results, Anisocytosis was observed in red blood cells 20 days after 5 Gy irradiation. Triangle and tetrapod were observed for small red blood cell types. Poikilocytosis, sickle-shaped Drepanocyte, and Acantocyte were observed in general-sized red blood cells. Schizocyte was observed in red blood cells 20 days after 7 Gy irradiation. Scanning electron microscope observation results, Dacryocyte was observed with microcytes. It was also confirmed that red blood cells were get tangled with each other. In addition, polygonal shapes and half-moon shapes were also observed. In conclusion, it is judged that the modified form of pathological study is more important than the numerical change in the study of red blood cells by radiation exposure. In conclusion, it was confirmed that modified morphological studies are more important than numerical changes in the study of red blood cells by radiation exposure.

• Applied Microscopy
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• v.18 no.2
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• pp.47-58
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• 1988

두가지 쌀 품종(品種) 종자(種子)(S-201, IR-8)의 호분층을 주사(走査) 및 투과(透過) 전자현미경(電子顯微鏡)으로 관찰(觀察)하면 구형(球形)과 결정형(結晶形)의 단백질체(蛋白質體)가 있는 것으로 밝혀졌으며, 구형(球形) 단백질체(蛋白質體)는 세포질내(細胞質內)에 존재(存在)하고 결정형(結晶形) 단백질체(蛋白質體)는 액포내(液胞內)에서 관찰(觀察)되었다. 가상적(假想的)인 한발 스트레스로서 열자극 처리(處理)($40^{\circ}C$ 에서 4시간)는 호분층(糊粉層)내에 단백질체(蛋白質體) 수에서 정상적(正常的)인 대조구보다 $40{\sim}50%$ 감소(減少)되었다. 또한 호분층(糊粉層)에서 단백질체(蛋白質體) 수의 감소(減少)는 IR-8품종(品種)보다 S-201품종(品種)에서 더욱 현저(顯著)하게 관찰(觀察)되었다. 열자극 처리(處理)로서 단백질체(蛋白質體) 수의 감소(減少)는 S-201품종(品種)에서 결정형(結晶形) 단백질체(蛋白質體)를 둘러싸고 있는 tonoplast membrane의 손상(損傷)으로 밝혀졌으며, 이런 손상(損傷)은 IR-8품종(品種)에는 좀 덜하다는 것으로 나타났다. 즉 이것은 S-201품종(品種)이 IR-8품종(品種)보다 열 자극(刺戟)(한발 스트레스)에 더욱 민감(敏感)하다는 것으로 사료된다. 두 품종(品種)의 종자(種子) 내배유(內胚乳)에 녹말(綠末)이 가득찬 주사(走査) 전자현미경(電子顯微鏡) 사진(寫眞)은 녹말(綠末)이 내배유(內胚乳)의 중앙(中央)으로부터 사출(査出)되는 hexagonal rods로 구성(構成)되어 있다는 것을 나타낸다. 이러한 hexagonal rods는 rods부터 쉽게 분쇄될 수 있는 triangular sectors로 구성(構成)되어 있으며, 이 sectors들의 각 내부(內部)는 $2{\sim}8$개의 단위(單位)로 구성(構成)되어 있는 커다란 compound starch grains들이 들어 있다. 이것은 쌀 내배유세포(內胚乳細胞)에서 compound starch drains들의 매우 다양한 크기를 설명(說明)하고 있다.

• Journal of the Mineralogical Society of Korea
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• v.1 no.2
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• pp.117-130
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• 1988

The morphology of the Ca-montmorillonites from the Gampo area was investigated by the use of scanning and transmission electron microscope. These bulk samples show an irregular or rugged surface with well developed cavities and relict outline of original ash material at low magnification by SEM, indicating that montmorillonites are derived from volcanogenic material. Two different types of morphology of montmorillonites by SEM were observed which appear to depend very much on the space available for crystal growth. One is honeycomb structure montmorillonite growing in an open space. The other is the closely packed aggregates of intergrown montmorillonite showing platy particles where available space for the growth is limited. Several different habits of montmorillonite within a single sample can be observed by TEM. The dominant habit observed is the irregularly shaped and foliated aggregates and the platy shaped particles. In general, platy shaped particles are relatively abundant in the samples from Yongdongri compared with those from Jugjeonri area.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.157-171
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• 1997

This study was conducted to see the effect of TiN ion-plating on the bond strength of orthodontic bracket. Three stainless-steel brackets with different base types were chosen; when TiN ion-plated brackets and non iorrplated brackets were bonded to the teeth, initial and long-term bond strength were measured, The observations oi bonding surface and failure sites through the scanning electron microscope were analysed and compared. The summary of this study was as follows; ${\cdot}$ When TiN ion-plating was not applied, the Micro-Loc type was the highest in bond strength atter 24 hours as $5.89{\pm}1.77$ MPa, followed by $4,27{\pm}1.12MPa$ for Foil Mesh type and $2.64{\pm}0.58MPa$ for Undercut type(P<0.05). ${\cdot}$ Under TiN ion-plating, the bond strength after 24 hours showed: Micro-Loc type $-6.26{\pm}1.51MPa$, Foil Mesh type $-7.45{\pm}2.01MPa$, Undercut type $-2.93{\pm}0.84MPa$. Unlike in the case of non ion-plating, Foil Mesh type showed a higher strength than Micro-Loc type, with Undercut type still showing the lowest bond strength(P<0.05). The bond strength, after 24 hours, increased in case of ion-plated in all 3 types, but a significant increase was shown only in Foil Mesh type(P<0.001). ${\cdot}$ Under a long-term immersion, regardless of ion or non ion-plating, bond strength in general increased over the initial bond strength(one day), with more stability. ${\cdot}$ Through scanning electron microscopic observation of bonding surface, it was found that, regardless of the bracket base type or the application of ion-plating, the resin was thoroughly spreaded into bracket base to form a solid bonding surface between the bracket and the tooth. This was also true in case of a long-term immersion. ${\cdot}$ The scanning electron microscopic observation of failure sites revealed diverse failure patterns.