• Title/Summary/Keyword: $B220^+$

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Effect of Texture of Al Single Crystal on the Nanopore Structure of AAO (알루미늄 단결정 집합조직이 AAO의 나노기공 구조에 미치는 영향)

  • Park, B.H.;Kim, I.
    • Transactions of Materials Processing
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    • v.29 no.3
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    • pp.127-134
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    • 2020
  • It is known that the difference of texture of the polycrystalline Al sheet is not a critical parameter for the formation of aligned nanopore arrays in anodic aluminum oxide (AAO). This will be related to the polycrystalline grain in the Al sheet. The texture of each grain in the polycrystalline Al sheet is different. The mixed textures of grains have the mixing effects on the nanopore structure of the AAO. Thus, the effect of Al texture on the nanopore structure of the AAO was investigated using three types of Al single crystals with (111), (200) and (220) textures in this paper. These three types of AAO layers were fabricated by the two-step anodizing method at 40 V and temperature of 0-5℃ in oxalic acid solution. In the nanopores formed on the AAO, the average area of one nanopore and the average roundness of one nanopore were measured were measured based on the SEM images. In the hexagon obtained by connecting nanopores on the AAO, the average standard deviation of one angle deviated from 120° was measured. In the AAO nanopores with texture of (111), (200) and (220) single crystal samples, the average area of one nanopore of (200) single crystal sample was the widest, followed by (111), (220) single crystals. The average circularity of one nanopore of (200) single crystal sample was the best, followed by (111), (220) single crystals. The average standard deviation of an angle from 120° of (220) single crystal sample was the largest, followed by (111) and (200) single crystals.

Effects of Mahaenggamseok-tang-gagambang on Immune Cells and Cytokines in OVA-Induced Asthmatic Mice (마행감석양가감방(麻杏甘石揚加減方)이 천식모델생쥐의 면역세포 및 사이토카인에 미치는 영향)

  • Park, Gil-Byeong;Park, Yang-Chun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.23 no.3
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    • pp.590-598
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    • 2009
  • The purpose of this research is to evaluate the effect of Mahaenggamseok-tang-gagambang (MGTG) on airway hyper- responsiveness (AHR), immune cells, cytokines and lung tissue in OVA-induced asthmatic mice. C578L/6 mice were injected, inhaled and sprayed with OVA for 12 weeks (3times a week) for asthma sensitization and challenge. Two experimental groups were treated with different concentrations of MGTG (400 mg/kg and 200 mg/kg) extract and cyclosporin A (10 mg/kg) for the later 8 weeks. Enhanced pause (Penh) levels were measured by whole body plethysmography. Immune cells were analyzed by flow cytometer in peripheral blood monocyte cell (PBMC) and lung cells. The IL-1b, IL-12, IFN-${\gamma}$, OVA-lgE, IL-4, IL-5, TNF-${\alpha}$ were analyzed by ELISA kit in serum and splenocyte+a-cCDS/a-CD28. Enhanced pause (Penh) levels of the MGTG groups (400 mg/kg and 200 mg/kg) were decreased significantly compared with that of control group. The numbers of MGTG groups (400 mg/kg and 200 mg/kg) on lung total cells were decreased significantly compared with that of control group. The numbers of MGTG groups (400 mg/kg and 200 mg/kg) on $CD3^+/CD69^+$, $B220^+/CD22^+$, $B220^+/CD23^+$, $B220^+/lgE^+$, $CCR3^+$ cells were decreased significantly compared with that of control group. The number of MGTG group (400 mg/kg) on $CD3^+/CD49b^+$ cells was decreased significantly compared with that of control group. The level of MGTG groups (400 mg/kg and 200 mg/kg) on IL-4, IL-5, IL-12, TNF-${\alpha}$, OVA-lgE were decreased significantly compared with that of control group. The level of MGTG group (400 mg/kg) on IL-1b, IL-1S, OVA-lgE were decreased significantly compared with that of control group. These results demonstrate that MGTG could be a desirable alternative therapy for allergic asthma by inhibiting the expression of immune cells, the activation of inflammatory mediator.

A New Pyranoxanthone Inophyllin B from Calophyllum inophyllum

  • Ee, G.C.L.;Kua, A.S.M.;Cheow, Y.L.;Lim, C.K.;Jong, V.;Rahmani, M.
    • Natural Product Sciences
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    • v.10 no.5
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    • pp.220-222
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    • 2004
  • A new prenylated pyranoxanthone, inophyllin B (1), was isolated from the roots of Calophyllum inophyllum (Guttiferae). Together with this compound was also isolated the known pyranoxanthone brasilixanthone B (2) and two common triterpenes friedelin (3) and sitosterol (4). Structural elucidations of these compounds were achieved through $^1H,\;^{13}C$, DEPT, COSY, HSQC and HMBC experiments. The molecular mass was determined using MS techniques. The crude extract indicated weak toxicity to the larvae of Aedes aegypti. We report here the isolation, structural elucidation and bioassay data for Inophyllin B and brasilixanthone B.

Ignition of Solid Propellants at Subatmospheric Pressures (대기압 이하에서 고체 추진제의 점화 특성 향상 연구)

  • Kim, In-Cul;Ryoo, Baek-Neung;Jung, Jung-Yong
    • Journal of the Korean Society of Propulsion Engineers
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    • v.10 no.3
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    • pp.67-72
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    • 2006
  • Several propellants were investigated experimentally for ignition characteristics in subatmospheric pressure. The threshold ignition pressure was 4 psia for HTPB/AP composite propellant. The partial replacement of AP in HTPB/AP propellant by $5{\sim}l5%$ of HMX, HNIW showed that the improvements in ignition delay was over 50% and the threshold pressure was below 0.4 psia. This appears to be due to the characteristics of HMX and HNIW exothermic dissociated at the temperature(${\sim}220^{\circ}C$) love. than that of AP. The ignition substance $B/KNO_3$ was coated thinly on the propellant surface for better ignition performance. As a result, ignition delay time of 15% was improved. NC is applied to $B/KNO_3$ ignition substance as a secondary binder and $NC-B/KNO_3$ suspension solution is coated to the propellant surface.

Design and Fabrication of Color Cube Prism for Display (디스플레이용 Color Cube의 설계 및 제작)

  • 우석훈;문진수;남성림;문일춘;강건모;황보창권
    • Proceedings of the Optical Society of Korea Conference
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    • 2002.07a
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    • pp.220-221
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    • 2002
  • 전달된 정보를 표시하는 다양한 디스플레이 광학기기 중 반사형 LCOS 프로젝션 시스템은 칼라의 구현을 위해 광원에서 나온 빔을 색분리계를 통해 각각 R, G, B 로 나누고, LC(Liquid Crystal)를 통해 각각의 이미지를 변조한 후 다시 합성하게 된다. 광원으로부터 입사한 백색 광선은 PBS(polarize beam splitter) array를 거쳐 s-편광파로 바뀌게 되고, 각각의 다이크로익 필터와 거울들을 거쳐 R, G, B의 3개의 채널로 분리된다. (중략)

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Theoretical Study of the Hydroalumination Reaction of Cyclopropane with Alane

  • Singh, Satya Prakash;Thankachan, Pompozhi Protasis
    • Journal of the Korean Chemical Society
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    • v.57 no.2
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    • pp.216-220
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    • 2013
  • The hydroalumination of cyclopropane has been investigated using the B3LYP density functional method employing several split-valence basis sets. It is shown that the reaction proceeds via an intermediate weakly bound complex and a four-centered transition state. Calculations at higher levels of theory were also performed at the geometries optimized at the B3LYP level, but only slight changes in the barriers were observed. Structural parameters for the transition state are also reported.

Semi-Insulating GaAs의 재료특성과 응용

  • 강광남
    • 전기의세계
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    • v.33 no.4
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    • pp.214-220
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    • 1984
  • 본고에서는 SI Ga As의 제조방법 및 전도매체들의 깊은 에너지위치(deep level)에 의한 상쇄현상(compensation)을 간략히 설명한 후 넓은 자장영역 (B=0-13T)에서의 Hall 효과 및 magnetoresistance (MR)에 의한 전기적 특성 연구방법을 설명하고, 전도매체의 재결합 현상을 연구할 수 있는 일반화 PME효과 (FA-PME)에 대해 기술한 후 SI Ga As 기판의 응용에 대해 간략히 기술하였다.

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