• 제목/요약/키워드: SEM Image

검색결과 507건 처리시간 0.033초

3D 프린터를 이용한 마이크로 리액터 가공에 관한 연구 (Fabrication of Micro-reactor by 3D Printing Machine)

  • 최해운;윤성철;마재권;방대욱
    • 한국생산제조학회지
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    • 제23권3호
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    • pp.218-222
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    • 2014
  • A 3D printer was used to fabricate a micro-TAS system for biomedical applications. A polymeric medical device fabrication based on a 3D printer can be performed at atmospheric conditions. A CAD- and CAM-based system is a flexible method to design medical components, and a 3D printer is a suitable device to perform this task. In this research, a 100-micron-wide fluidic channel was fabricated with a high-aspect ratio. A cross-sectional SEM image confirmed its possible usage in a micro-reactor using 3D printers. CNC-machined samples were compared to 3D printer-fabricated samples, and the advantages and disadvantages were discussed. Based on the SEM images, the surface roughness of the 3D printed reactor was not affected by wet or dry conditions due to its manufacturing principle. An aspect ratio of 5 to 1 was achievable with 100-${\mu}$ m-wide fluid channels. No melting was found, and the shape of channels was straight enough to be used for micro reactors.

A Study of Hair Damage by Magic Straight Perm

  • Lim, Sun-Nye
    • Applied Microscopy
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    • 제42권3호
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    • pp.129-135
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    • 2012
  • In this study, the changes in hair quality before and after Magic straight perm have been evaluated through a hair damage measurement method. For this, a healthy high school student's (age18 years) wavy hair was selected and permed on the left and right sides. Then, the changes caused by physical methods which were applied during the fl at iron-based Magic straight perm were evaluated based on the hair damage measurement method before and after the Magic straight perm. According to the protein release test after the Magic straight perm, 1.26% in average and 0.14% was observed in Cool Magic straight perm sample. In a field emission scanning electron microscopy (FE-SEM) test, saw teeth-shaped partial desquamation of cuticle cells and impurities were observed in the warm-treated hair sample. In atomic force microscope (AFM), line-profile is a method to represent roughness data on hair. According to analysis on 3-dimensional (3D) images, the hair with Cool Magic straight perm was lower than the hair with Warm Magic perm in terms of the color change of 3D images. In addition, vertical changes were observed in the hair with Cool Magic perm. As a result, irregular surface roughness was observed. This study proposed a method to minimize hair damage by cooling down the heat with the cool hair straightener as soon as the Warm Magic was finished.

산화제 결핍 상태의 프로판 층류 확산화염에서 LIF 이미지와 SiC 필라멘트 부착물의 형태 비교 (Comparison of Morphology of Deposits on SiC Filaments with LIF Image in Propane/Air Laminar Diffusion Flames in an Oxidizer Deficient Environment)

  • 심성훈;유창종;신현동
    • 한국연소학회지
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    • 제7권4호
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    • pp.1-9
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    • 2002
  • The morphology of deposits on $15-{\mu}m$ thin SiC filaments has been investigated with SEM and compared with UV-excited laser induced broadband fluorescences in co-flowing, propane laminar diffusion flames in a reduced oxidizer environment. The homogeneous morphology of droplet-like deposits inner flame zone and the agglomeration of condensed-phase deposits and the transition to soots from grown up droplet-like precursors with approaching the flame surface can be observed in a barely sooting flame. The average size of the mature soots deposited in the luminous flame edge is scarcely dependent on their axial position in a confined flame under reduced oxidizer condition. A double structure of PAH fluorescence is observed in near-extinction flames with further decreasing of oxidizer. A comparison of the PAH fluorescence with the morphologies of deposits indicates that appearance of the "dark" hollow zone is caused by a decreased number density of developed liquid-phase large molecules and the outer weak fluorescence zone is caused by the diffusion of gas-phase small molecules.

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조선왕조실록 태백산사고본 표지 및 내지의 비파괴적 특성 연구 (Non-Constructive analysis for the cover and inner paper in the Taebaeksan volume of Joseon Dynasty annals)

  • 조정혜;김강재;엄태진
    • 펄프종이기술
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    • 제42권3호
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    • pp.28-36
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    • 2010
  • Today We have three full series of the annals of Joseon Dynasty. Taebaeksan volume which is one of them shows comparatively good maintenance but Taebaeksan volume also decomposed in patches. The size of cover and inner paper were increased in late Joseon Dynasty, but the weight, thickness and basis weight bears no relation to each other. The oxidation index of paper in annals of pre-periods of King Sunjo shows very high value. After the annals of King Sunjo, the oxidation index of paper is very similar to today's Hanji. L.a.b values of inner paper in the Taebaeksan volume are similar generally. The average length of fiber using image analysis soft ware is 8.08~9.92 mm, that like immediate value of measurement. The air fraction of fiber's range is 1.20~2.12%. It lower than today's Hanji. After considering the factors of the length of fiber, air fraction and FE-SEM, we reached that no difference between raw material of inner paper in the Taebaeksan volume.

Chitosan 으로 처리(處理)된 모발(毛髮)의 물리적(物理的) 특성(特性) (Physical Property of Hair Fiber Treated with Chitosan)

  • 김경선;전동원;김종준;안병태
    • 패션비즈니스
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    • 제11권5호
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    • pp.51-63
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    • 2007
  • Chitosan, a natural cationic macromolecular material, has been known for its moisturizing and healing effect due to the coating action based on strong ionic bonding when the chitosan is treated on hair strands. In this study, the acidic aqueous chitosan solution was prepared to treat healthy hair, and damaged hair due to bleaching, relatively thin hair and thick hair specimens. The chitosan treatment effect was reviewed by comparing spectrophotometric and mechanical characteristics of the chitosan treated and untreated specimens. Electrostatic voltage was somewhat reduced after the chitosan treatment. Smoothly coated surface was observed, in the SEM images, especially for damaged hair specimens. The values of breaking strength, which is one of the indicators of the internal characteristics of hair, was high in the case of chitosan treated samples. The values of elongation was also high in the case of chitosan treated samples, which proves the chitosan treatment effect. The friction force, one of the indicators of surface characteristics, was reduced for the case of chitosan treated samples.

플라즈마를 이용한 분말형 금속 연료 알루미늄의 점화 특성 (Ignition Characteristics of Aluminum Metal Powder Fuel with Thermal Plasma)

  • 이상협;임지환;윤웅섭
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2011년도 제37회 추계학술대회논문집
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    • pp.737-744
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    • 2011
  • 탄화수소 계열의 점화원과 달리 선행 연구된 스팀 플라즈마 점화기를 이용한 알루미늄 분말의 지속 연소 성공을 바탕으로, 고온의 플라즈마를 이용한 알루미늄 분말의 점화 특성을 알아보기 위해 산화제가 없는 환경을 조성하여 점화 특성 확인 실험을 수행하였다. 아르곤 플라즈마를 이용하여 이전의 연소 실험과 동일한 4500 K의 온도 조건 및 이송 가스를 이용한 입자 공급 조건을 조성하여 실험을 수행하였으며, 플라즈마의 온도는 방출분광법을 사용하여 측정하였고 점화 특성은 SEM 촬영과 EDS 분석을 통해 비교 분석하였다. 고온의 플라즈마 제트 내부를 통과한 알루미늄 분말은 탄화수소 계열의 점화원과 다르게 급격한 기화로 인한 점화 촉진 효과를 확인 할 수 있었다.

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해양의료관광지의 방문의도에 관한 탐색적 연구 (An Exploratory Study on Visit Intention of Destination in Marine Health Tourism)

  • 김민철;부창산
    • 수산해양교육연구
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    • 제27권1호
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    • pp.230-242
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    • 2015
  • The purpose of this study is to propose, firstly, the definition of marine health tourism and empirically to analyse the effect of benefit sought and brand equity on visit intention of destination as marine health tourism. This study utilizes the PLS-SEM method in order to measure the overall model fitness level and statistical significance of all paths in proposed research model. As a result of the analysis, benefit sought factor like nature has a highest positive effect on brand equity(image and perceived quality) and also, on visit intention via brand equity. Specially, this study measures the non-linear of all the paths and shows the statistical significance that the more high health factor as benefit sought is, the preference for quality brands is more steeply. In addition, the measurement of the moderating effect of gender variables shows that female is the most sensitive than male on the path from health benefit sought to brand quality among all the paths. However, the definition of marine health tourism in this study is proposed according to the characteristics of a particular area. In this vein, the definition is needed to generalize more through follow-up study.

연소합성법으로 제작한 $Y_3Al_5O_{12}:Eu^{3+}$ 나노형광체의 광학적 특성 (Photoluminescence Characteristics of $Y_3Al_5O_{12}:Eu^{3+}$ Nano-Phosphors by Combustion Method)

  • 곽현호;김세준;박용서;최형욱
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
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    • pp.406-407
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    • 2008
  • For this study, Yttrium aluminum garnet (YAG) particles doped $Eu^{3+}$ ions were prepared via the combustion process using the 1:1 ratio of metal ions to reagents. The characteristics of the synthesized nano powder were investigated by means of X-ray diffraction (XRD), Scanning Electron Microscope (SEM), and photoluminescence (PL). The various YAG peaks, with the (420) main peak, appeared at all sintering temperature XRD patterns. The YAG phase crystallized with results that are in good agreement with the JCPDS diffraction file 33-0040. The SEM image showed that the resulting YAG:Eu powders had larger sizes with the increse in the sintering temperature. The grain size was about 50nm at $1000^{\circ}C$. The PL intensity of $Eu^{3+}$ has the line peaks of 598, 610, 632nm and has main peak at 591nm.

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유한요소해석과 광선추적을 연계한 주사전자 현미경 대물렌즈의 설계 및 해석 (Design and Analysis of an Objective Lens for a Scanning Electron Microscope by Coupling FE Analysis and Ray Tracing)

  • 박근;이재진;박만진;김동환;장동영
    • 한국정밀공학회지
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    • 제26권11호
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    • pp.92-98
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    • 2009
  • The scanning electron microscope (SEM) contains an electron optical system in which electrons are emitted and moved to form a focused beam, and generates secondary electrons from the specimen surfaces, eventually making an image. The electron optical system usually contains two condenser lenses and an objective lens. The condenser lenses generate a magnetic field that forces the electron beams to form crossovers at desired locations. The objective lens then focuses the electron beams on the specimen. The present study covers the design and analysis of an objective lens for a thermionic SEM. A finite element (FE) analysis for the objective lens is performed to analyze its magnetic characteristics for various lens designs. Relevant beam trajectories are also investigated by tracing the ray path of the electron beams under the magnetic fields inside the objective lens.

SPME를 이용한 Geosmin과 2-MIB분석 시 잔류염소의 영향에 관한 연구 (Effect of Residual Chlorine on the Analysis of Geosmin and 2-MIB Using SPME (Solid Phase Microextraction))

  • 김성진;홍성호;민달기
    • 상하수도학회지
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    • 제19권6호
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    • pp.713-719
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    • 2005
  • SPME (Soild phase microextraction) has been used in the analysis of many volatile organic compounds, such as geosmin and 2-methylisoborneol (2-MIB), trihalomethanes (THMs) in drinking water. SPME fiber is characterized by high adsorption capacity (DVB/CAR/PDMS, DVB/PDMS etc.). Although the highly active adsorption capacities of the SPME fiber are often to the chemical functional group, surface properties play a significant role in determining the surface adsorption capacities. The objectives of this study were to evaluate effect of residual chlorine on analysis of geosmin and 2-MIB. Image taken by SEM before preloaded with chlorine, the surface and porous media was almost perfect spherical shape and no clogging of pores. However, after preloaded with chlorine the surface was aggregated and pore was blocked. The recovery rate of geosmin and 2-MIB coexisting with chlorine was reduced by 35 to 62%. The recovery rate with preloaded with chlorine was reduced by 25 to 43%. The lower concentration of geosmin and 2-MIB and the higher concentration of chlorine existed in water, the lower the recovery rate was.