• Title/Summary/Keyword: columnar type

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Saturation Characteristics of a Boron-lined ionization Chamber

  • Chae, Sung-Ki
    • Nuclear Engineering and Technology
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    • v.5 no.2
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    • pp.94-102
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    • 1973
  • Saturation characteristics of a current-type ionization chamber are investigated theoretically and experimentally in the columnar recombination region. The experiments were performed using a boron-lined cylindrical ionization chamber filled with nitrogen or helium at pressures of 760 mmHg and 380 mmHg. The collection efficiency deduced from the analytical method is in good agreement with the experimental results. This theory makes it possible to predict saturation characteristics for all ionization intensities with only the design data.

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Evaluation of ferritic stainless steel FCA overlay weld metal ductility (페라이트계 스테인리강의 FCA 육성용접부 연성 평가)

  • Kim Yeong-Il;Choi Jun-Tae;Kim Dae-Sun
    • Proceedings of the KWS Conference
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    • 2006.05a
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    • pp.140-142
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    • 2006
  • The bend ductility of Type 410S ferritic stainless steel overlay weld on carbon steel was investigated. Overlay weld that was stabilized with Nb had large columnar ferrite grain and Nb precipitate on grain boundary. And that caused fracture when bend test without concern of PWHT condition. Proper bend ductility at as-welded condition was achieved by refining ferrite grain with addition of $0.04{\sim}0.09%$ Al and $0.2{\sim}0.5%$ Ti that make oxide, carbide and nitride at high temperature.

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Effect of Ar Flow Ratio on the Characteristics of Al-Doped ZnO Grown by RF Magnetron Sputtering (마그네트론 스퍼터를 이용한 Ar 가스 유량 조절에 따른 AZO의 특성 변화)

  • Lee, Seung-Jin;Jeong, Young-Jin;Son, Chang-Sik
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.11a
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    • pp.61.2-61.2
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    • 2011
  • 본 연구에서는 박막 태양전지용 투명전극으로 사용하기 위해서 Gun-type RF 마그네트론 스퍼트링을 이용하였다. 챔퍼안의 타겟은 AZO타겟(Zn: 98[wt.%], Al:2[wt.%]을 장착하였고 공정압력은 고진공을 유지하였다. 온도는 $300^{\circ}C$로 고정하였고 전력은 70W로 고정하였다. $Ar^+$ 가스유량비를 20sccm~100sccm으로 변화를 주어 기판 위에 AZO를 증착하여 AZO의 구조적 및 광학적 특성의 의존성을 알아보았다. 모든 가스변화에서 400에서 700 nm까지의 가시광 영역에서의 AZO 박막의 평균 투과도는 약 85% 이상의 우수한 투과율을 보인다. AZO 박막 내의 결정 구조는 (002)면으로 우선 배향을 하는 wurtzite 구조를 가지며, $Ar^+$변화에 의해 두께가 증가하면서 결정립의 주상 (columnar) 성장이 향상되고 결정립의 크기도 증가한다. 이러한 경향성은 $Ar^+$변화에 의해 결정성이 향상된다는 것을 의미한다. 이와 같은 구조 및 광학 특성을 가지는 유리 기판 위에 증착된 AZO는 박막 태양전지용 투명 전극으로 응용이 가능할 것이다.

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The Study on the Behavior of TiN Thin Film Growth According to Deposition Pressure in PECVD Process (플라즈마 화학 증착에서 증착압력에 따른 TiN 박막의 성장거동)

  • Lee, Z.H.;Nam, O.H.;Lee, I.W.;Kim, M.I.
    • Journal of the Korean Society for Heat Treatment
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    • v.5 no.2
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    • pp.95-102
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    • 1992
  • In this study, we tried to describe the quantitative model of TiN film structure which was deposited by PECVD process. The macro-grain growth behavior was studied at the various deposition pressures and times. As a result, It was confirmed that TiN films had the typical Zone 1 structure, and macro-columnar grains were, without reference to the deposition pressure, grown ballistic type by the growth-death competition following the equation, $Y=aX^2$, approximately obtained by regression analysis. Also, the thickness and the crystallization of TiN thin films were increased, the chlorine contents were decreased according to the decreasing of deposition pressure.

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Ultrastructure of Endocrine Cells in the Midgut Epithelium of the Japanese Cockroach, Periplaneta japonica (집바퀴의 중장 상피조직내에 있는 내분비세포의 미세구조)

  • Yu, Chai-Hyeock
    • Applied Microscopy
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    • v.26 no.4
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    • pp.421-430
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    • 1996
  • The endocrine cells in the midgut epithelium of the Japanese cockroach, Periplaneta japonica were observed by the light and electron microscopy. The midgut epithelium of the last instar larva and adult cockroach consisted of principal columnar cells, regenerative cells, and secretory granular cells. Midgut endocrine cells were positioned basally as a cone-shaped single cell in the epithelium or underneath the regenerative crypt cells. When midgut epithelium grows and the cell composing it transforms, between the endocrine cells and regenerative cells were made desmosome type junction and large vesicular shaped stretches of loose contact. The endocrine cells were characterized by a clear cytoplasm with abundant Golgi complex and numerous secretory granules. The secretory granules in the cell were spherical and electron dense with their diameter of $200{\sim}400nm$. The secretory granules have been observed as discharged by exocytosis on the basal and lateral side of the cell.

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A Study on the Deteriorated Cause Analysis of Mold Type Potential Transformer (몰드형 계기용 변압기의 소손원인 해석에 관한 연구)

  • Choi, Chung-Seog;Kim, Hyug-Soo;Shong, Kil-Mok;Kim, Hyung-Rae;Lee, Duck-Chool
    • Proceedings of the KIEE Conference
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    • 2000.07c
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    • pp.1557-1559
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    • 2000
  • In this paper, we intend to establish the judgement of electrical fire through analysis of PT(Potential Transformer) using the power installation. The columnar structure and the void generated by abrupt heat grew at the tenter of boundary-face on the metallurgical microscope analysis. The detection of OK lines was confirmed by EDX(Energy Dispersive X-ray spectroscopy) as melting and recombination due to the layer-short of the wiring. We found that the thermal-weight decrease occurred at 300$^{\circ}C$ in case of being the thermal-deterioration on the base of the result that analyzed the insulated-materials by using TGA, and the thermal reaction limited-value of PT insulator was about 300$^{\circ}C$ on the DSC curve. As this analysis, we confirmed what the layer-short appeared in the wiring of PT.

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A Case of Papilloma in the Nasal Cavity (비강내에 발생한 유두종 1례)

  • 김홍권;김성숙;김영복;박수만
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1981.05a
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    • pp.12.2-12
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    • 1981
  • The papilloma of the nose and the sinuses is uncommon benign neoplasm that was pro bably first described by Billroth in 1855 as a "villiform cancer": It may polypoid or papillomatous in the nose or sinuses and is frequently multiple. Clinically, there are 3types of the papilloma found in the nasal cavity and sinuses, vestibule, fungiform, inverting. The vestibular type is the keratotic lesion arise from the squamous epithelium lining the vestibule of the nose. The inverting type, which is covered by the columnar or metaplastic squamous epithelium is pliable, pink and tends to bleed quite easily. The fungiform type is covered by the stratified squamous epithelium which shows varying degree of cornification. It is more caulflow like than the inverting type and does not bleed easily. Recently, the authors experienced a case of the fungiform type papilloma which occupied right nasal cavity and nasopharynx. So, we reports the case, with review of the current brief literatures. A 55 year old man was admitted with the chief complaints of right nasal obstruction by the protruded movable mass on right nasal cavity, which was noticed about 7 months ago. The biopsy report revealed fungiform type papilloma.(length 18cm. width 2.5 cm. weight 41 gr.) The tumor mass was removed surgically through intranasal approach under the general anesthesia. Postoperative course was uneventful and the patient was discharged after 7 days hospitalization. No evidence of recurrence has been observed up to date.

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Influence of Heat-Treatment on the Adhesive Strength between a Micro-Sized Bonded Component and a Silicon Substrate under Bend and Shear Loading Conditions

  • Ishiyama, Chiemi
    • Journal of the Korean Society for Nondestructive Testing
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    • v.32 no.2
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    • pp.122-130
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    • 2012
  • Adhesive bend and shear tests of micro-sized bonded component have been performed to clarify the relationship between effects of heat-treatment on the adhesive strength and the bonded specimen shape using Weibull analysis. Multiple micro-sized SU-8 columns with four different diameters were fabricated on a Si substrate under the same fabrication condition. Heat-treatment can improve both of the adhesive bend and shear strength. The improvement rate of the adhesive shear strength is much larger than that of the adhesive bend strength, because the residual stress, which must change by heat-treatment, should effect more strongly on the shear loading. In case of bend type test, the adhesive bend strength in the smaller diameters (50 and $75\;{\mu}m$) widely vary, because the critical size of the natural defect (micro-crack) should vary more widely in the smaller diameters. In contrast, in case of shear type test, the adhesive shear strengths in each diameter of the columns little vary. This suggests that the size of the natural defects may not strongly influence on the adhesive shear strength. All the result suggests that both of the adhesive bend and shear strengths should be complicatedly affected by heat-treatment and the bonded columnar diameter.

국내 자생식물의 유기용매추출물로부터 양파부패균 Penicillium sp. ON-211에 대한 항균활성 검정

  • Ha, Cheol-Gyu;Tae, Eon-Hui;Gang, Seon-Cheol
    • 한국생물공학회:학술대회논문집
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    • 2000.11a
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    • pp.729-732
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    • 2000
  • Antifungal activities of domestic plants were examined to develop natural anti-microbial agents, able to protect onion from spoiling microorganisms during their storage. A fungus was isolated from spoiling onion and identified to Penicillium sp. ON-211, based on the morphological characteristics of conidiophore and conidia. Chloroform extracts of Juniperus chinesis Linnaeus, Juniperus. chi. var. horizontalis, water extract of Thujs orientalis Linnaeus' seed and the n-hexane extract of Juniperus. chi. var. horizontalis N. showed remarkable antifungal activties against this fungus.

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The Effect of Hydrogen in the Nuclear Fuel Cladding on the Oxidation under High Temperature and High Pressure Steam (고압 수증기하 산화에서 핵연료 피복관내 수소효과 연구)

  • Jung, Yunmock;Jeong, Seonggi;Park, Kwangheon;Noh, Seonho
    • Journal of the Korean institute of surface engineering
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    • v.47 no.1
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    • pp.7-12
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    • 2014
  • The characteristics of oxidation for the Zry-4 was measured in the $800^{\circ}C$ and high steam pressure (50 bar, 75 bar, 100 bar) conditions, using an apparatus for high pressure steam oxidation. The effect of accelerated oxidation by high-pressure steam was increased more than 60% in hydrogen-charged cladding than normal cladding. This difference between hydrogen charged claddings and normal claddings tends to be larger as the higher pressure. The accelerated oxidation effect of hydrogen charging cladding is regarded as the hydrogen on the metal layer affects the formation of the protective oxide layer. The creation of the sound monoclinic phase in Zry-4 oxidation influences reinforcement of corrosion-resistance of the oxide layer. The oxidation is estimated to be accelerated due to the creation of equiaxial type oxide film with lower corrosion resistance than that of columnar type oxide film. When tetragonal oxide film transformed into the monoclinic oxide film, surface energy of the new monoclinic phase reduced by hydrogen in the metal layer.