• Title/Summary/Keyword: light microscope

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Fabrication and Linear & Nonlinear Optical Characterization of Photonic Crystals (포토닉 밴드갭 광결정의 제작과 선형 및 비선형 광학 특성 연구)

  • Ha Na Yeong;U Yeon Gyeong;Hwang Ji-Su;Jang Hye-Jeong;Park Byeong-Ju;U Jeong-Won
    • Proceedings of the Optical Society of Korea Conference
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    • 2002.07a
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    • pp.162-163
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    • 2002
  • 1-D photonic band-gap structure is identified in a cholesteric liquid crystal system. The optical transmission spectrum is measured and compared with the theoretical analysis. Nonlinear transmission is measured near the band edge. Also 3-D photonic band-gap structures are fabricated from dielectric colloidal polystyrene beads through a centrifuge method. The fabricated photonic crystals exhibit opalescent colors under white light and show a clear diffraction peak dependent on the incident angle of the light beam. Also the scanning electron microscope image was taken to verify the face-centered cubic crystal structure. Bragg's law and Snell's law are employed to describe the position of angle resolved diffraction peaks. It was shown that the optically deduced effective refractive index and lattice constants were in good agreement with the crystal structure identified by scanning electron microscope.

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Light and Scanning Electron Microscope Observatt-ons on Sexual Dimorphism in Pupa of Mullberry silkworm, bombyx Mori Linn (Lopidoptera : Bombycidae)

  • Kumar, Vineet;Tewari, S.K.;Awasthi, A.K.;Datta, R.K.
    • Journal of Sericultural and Entomological Science
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    • v.41 no.2
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    • pp.87-93
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    • 1999
  • Under Light and Scanning electron microscope, the pupal morphology of mulberry silkworm Bombyx mori Linn. revealed the prothorax and metathorax, well developed mesothorax, less defined last pair of sporacle, well exposed prothoracic femora and wing pads approaching the anterior margin of Ab III. The important sex separating characters viz, wegiht, antennal elevations, intersegmental lines and genings have discussed. Further, two separate openings bursa copulatrix and ovipositional opening were observed, performing different functions in abult moth.

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Fabrication and Optical Characterization of Colloidal 3-D Photonic Crystals

  • N. Y. Ha;Y. Woo;Park, Byungchoo;J. W. Wu
    • Journal of the Korean Vacuum Society
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    • v.12 no.S1
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    • pp.15-16
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    • 2003
  • 3-D photonic band-gap structures are fabricated from dielectric colloidal polystyrene beads through a centrifuge method. The fabricated photonic crystals exhibit opalescent colors under white light and show a clear diffraction peak dependent on the incident angle of the light beam. Also the scanning electron microscope image was taken to verify the face-centered cubic crystal structure. Bragg's law and Snell's law are employed to describe the position of angle resolved diffraction peaks. It was shown that the optically deduced effective refractive index and lattice constants were in good agreement with the crystal structure identified by scanning electron microscope.

경북동해안산화석규조의 미세구조에 관한 전자현미경적관찰

  • 안영필
    • Journal of Plant Biology
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    • v.3 no.2
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    • pp.26-28
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    • 1960
  • Electron-Microscopical Observalion on Fine Structure of Diatom Frustules which is collected in the East Coast of Kyung-Pook Province. Kor. Jour. Bot. 3(2) 26-28 lllus. 1960 The fine structure of Diatom frustules which is collected in the east coast of Yungil and Wul Sung, Kyung-Pook Province, is ovserved by the light microscope and hte electron-microscope, and the materials collected by auther are 1 family, 2 genus and 2 species. Coscinodiscus elegans. Greville Actinoptychus undulatus Rals Those were havitated in sea water as the plankton which were found in diatomite.

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Studies on the Nitrogen-fixing Symbiosis in Actinorhizal Plants I. Survey of the actinorhizal root nodules and collection the root nodules (목본식물에 있어서 질소고정 공생관계 (Actinorhizal symbiosis)에 관한 연구)

  • 안정선
    • Journal of Plant Biology
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    • v.29 no.2
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    • pp.109-115
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    • 1986
  • Actinorhizal plants being capable of fixing atmospheric nitrogen in symbiotic association with Frankia were surveyed for their root nodules, and the root nodules were collected for further studies. Three species of Alnus and Elaeagnus (A. hirsuta, a. firma, A. japonica; E. glabra, e. umbellata, E. macrophylla) and one species of Myrica (M. rubura) were confirmed to bear the root nodules of typical external shape. Morphological studies using light microscope and scanning electron microscope revealed the presence of vesicle clusters in the cortex region of the root. Two tentative endophyte colonies were isolated from the root nodule of A. hirsuta.

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주사전자현미경을 이용한 섬유의 결점분석(1)

  • 이석영;조인술
    • Textile Coloration and Finishing
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    • v.7 no.4
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    • pp.116-121
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    • 1995
  • 인간의 욕구는 무한하다고 한다. 이 무한한 욕구를 충족시켜 주기 위하여 많은 연구가 행하여져 왔으며, 오늘날과 같은 과학의 발달을 가져오게 되었다. 그 중에서도 눈에 보이지 않는 조그마한 물체를 보고 싶어하는 욕망을 충족시키기 위한 연구를 거듭한 결과 렌즈를 통한 빛의 굴절 작용을 이용하여 미세한 물체를 확대하여 보는 광학현미경(Light Microscope 또는 Optical Microscope)이 개발되었다. 그러나 과학의 발달로 인한 여러가지 현상의 다양활를 관찰하기에는 광학현미경의 기능만으로는 한계점에 도달하게 되었다. 이 기능을 향상시키기 위하여 광원을 빛 대신 파장이 매우 짧은 전자선을 이용한 전자현미경이 개발되었다.

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Kinetic Study of the Visible Light-Induced Sonophotocatalytic Degradation of MB Solution in the Presence of Fe/TiO2-MWCNT Catalyst

  • Zhang, Kan;Oh, Won-Chun
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1589-1595
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    • 2010
  • In order to effective degradation of organic dye both under visible light or ultrasonic irradiation, the MWCNTs (multiwalled carbon nanotube) deposited with Fe and $TiO_2$ were prepared by a modified sol-gel method. The Fe/$TiO_2$-MWCNT catalyst was characterized by surface area of BET, scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), and energy dispersive X-ray (EDX) and ultraviolet-visible (UV-vis) spectroscopy. The low intensity visible light and low power ultrasound was as an irradiation source and the methylene blue (MB) was choose as the model organic dye. Then degradation experiments were carried out in present of undoped $TiO_2$, Fe/$TiO_2$ and Fe/$TiO_2$-MWCNT catalysts. Through the degradation of MB solution, the results showed the feasible and potential use of Fe/$TiO_2$-MWCNT catalyst under visible light and ultrasonic irradiation due to the enhanced formation of reactive radicals as well as the possible visible light and the increase of ultrasound-induced active surface area of the catalyst. After addition of $H_2O_2$, the MB degradation rates have been accelerated, especially with Fe/$TiO_2$-MWCNT catalyst, in case of that the photo-Fenton reaction occurred. The sonophotocatalysis was always faster than the respective individual processes due to the more formation of reactive radicals as well as the increase of the active surface area of Fe/$TiO_2$-MWCNT catalyst.

Relative Photonic Properties of Fe/TiO2-Nanocarbon Catalysts for Degradation of MB Solution under Visible Light

  • Oh, Won-Chun;Zhang, Feng-Jun;Meng, Ze-Da;Zhang, Kan
    • Bulletin of the Korean Chemical Society
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    • v.31 no.5
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    • pp.1128-1134
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    • 2010
  • Nanocarbon supported Fe/$TiO_2$ composite catalysts were prepared using CNTs (carbon nanotubes) and $C_{60}$ (fullerene) as nanocarbon sources by a modified sol-gel method. The Fe/$TiO_2$-nanocarbon composites were characterized by the BET surface area, scanning electron microscope (SEM), Transmission Electron Microscope (TEM), X-ray diffraction (XRD), energy dispersive X-ray (EDX) and UV-vis spectra. In comparison with non-nanocarbon doped Fe/$TiO_2$ composites, the nanocarbon supported Fe/$TiO_2$ composites had higher absorption ability with a larger specific surface area, and showed higher photocatalytic activity during the degradation of methylene blue (MB) under visible light. The reasons for the obvious increase of photocatalytic activity indicated that the photoactivity not only benefits from nanocarbon introduced, but also relates to the cooperative effect of the Fe as a dopant.

Fabrication of Plasmon Subwavelength Nanostructures for Nanoimprinting

  • Cho, Eun-Byurl;Yeo, Jong-Souk
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.247-247
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    • 2012
  • Plasmon subwavelength nanostructures enable the structurally modulated color due to the resonance conditions for the specific wavelength range of light with the nanoscale hole arrays on a metal layer. While the unique properties offered from a single layer of metal may open up the potential applications of integrated devices to displays and sensors, fabrication requirements in nanoscale, typically on the order of or smaller than the wavelength of light in a corresponding medium can limit the cost-effective implementation of the plasmonic nanostructures. Simpler nanoscale replication technologies based on the soft lithography or roll-to-roll nanoimprinting can introduce economically feasible manufacturing process for these devices. Such replication requires an optimal design of a master template to produce a stamp that can be applied for a roll-to-roll nanoimprinting. In this paper, a master mold with subwavelength nanostructures is fabricated and optimized using focused ion beam for the applications to nanoimprinting process. Au thin film layer is deposited by sputtering on a glass that serves as a dielectric substrate. Focused ion beam milling (FIB, JEOL JIB-4601F) is used to fabricate surface plasmon subwavelength nanostructures made of periodic hole arrays. The light spectrum of the fabricated nanostructures is characterized by using UV-Vis-NIR spectrophotometer (Agilent, Cary 5000) and the surface morphology is measured by using atomic force microscope (AFM, Park System XE-100) and scanning electron microscope (SEM, JEOL JSM-7100F). Relationship between the parameters of the hole arrays and the corresponding spectral characteristics and their potential applications are also discussed.

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